Firehouse Subs Brownie Recipe

Firehouse subs brownie recipe has been something I’ve been searching for – one that’s chewy, fudgy, and loaded with chocolate flavor.

I’ve tried a few suggestions from friends, but one in particular caught my attention. A close friend of mine, who’s both a passionate foodie and a talented food blogger, told me I had to try the brownie from Firehouse Subs.

The first bite was amazing – rich, soft, and bursting with deep chocolate goodness. The texture was moist and fudgy, with big chocolate chunks melting into every bite.

It quickly became one of my favorites. After browsing food blogs and testing a few versions in my kitchen, I finally found the recipe that tastes just like the original.

Today, I’m sharing this copycat Firehouse Subs brownie Recipe so you can enjoy it at home too.

Why You’ll LOVE This Recipe

You will love this recipe because it is easy and true to that rich, chewy brownie you want. I keep the steps simple so you can make them without stress.

You do not need fancy tools. You do not need hard-to-find items. The mix of melted dark chocolate, cocoa powder, and two kinds of sugar gives the brownies a deep chocolate taste.

I like how the top gets a pretty crinkled shine while the inside stays fudgy. You can change the mix a little and still get great results.

I make this when I want a fast treat that tastes close to the shop version.

Firehouse Subs Brownie Recipe Ingredients

• 105g dark chocolate – I use 50% dark chocolate for the best flavor. You can substitute with semi-sweet chocolate chips if you can’t find bar chocolate. Just chop them into bigger pieces.
• 3/4 cup all-purpose flour – Regular flour works perfectly. Don’t use cake flour as it will make the brownies too soft. You can substitute with gluten-free flour blend if needed.
• 1/2 tsp salt – This helps balance all the sweetness and makes the chocolate taste stronger. Use regular table salt.
• 113g unsalted butter – Room temperature butter works best. You can use salted butter but reduce the salt to 1/4 teaspoon.
• 1/4 cup unflavored vegetable oil – This keeps the brownies moist. Canola oil or melted coconut oil work too.
• 1 cup white granulated sugar – Regular white sugar is perfect. Don’t substitute with powdered sugar.
• 1/2 cup packed soft brown sugar – Light brown sugar gives the best flavor. Dark brown sugar works but makes the taste stronger.
• 2/3 cup cocoa powder – Use unsweetened cocoa powder only. Dutch-process or natural both work great.
• 1 tsp coffee powder – Instant coffee powder boosts the chocolate flavor. You can skip this if you don’t have any.
• 1 tsp vanilla essence/extract – Pure vanilla extract tastes better than artificial vanilla.
• 2 large eggs – Room temperature eggs mix better. You can use 3 medium eggs instead.

Equipment You May Need

1. 8-inch square cake tin – Perfect size for thick, fudgy brownies. Metal pans work best for even baking.
2. Pastry brush – For greasing the pan evenly with butter or oil.
3. Baking paper – Prevents sticking and makes removing brownies super easy.
4. Chopping board – For cutting the chocolate into chunks safely.
5. Sharp knife – Cuts chocolate cleanly and slices finished brownies neatly.
6. Large mixing bowl – Holds all ingredients comfortably while mixing.
7. Fine-mesh sieve – Removes lumps from flour and cocoa powder for smooth batter.
8. Fork for mixing – Simple tool for stirring dry ingredients together.
9. Microwave-safe bowl – Glass or ceramic bowl that won’t melt when heating chocolate mixture.
10. Microwave – Quick way to melt butter and chocolate mixture evenly.
11. Rubber spatula – Flexible tool perfect for gentle folding without overmixing.
12. Hand mixer or stand mixer – Whips eggs and sugar to light, creamy texture for crinkly tops.
13. Wire cooling rack – Allows air circulation for even cooling after baking.

How To Make Firehouse Subs Brownie Recipe

Step 1 | Get Your Oven Ready

Start by heating your oven to 320°F (160°C) with the fan on. Grease an 8-inch square cake tin with butter, then line it with baking paper, leaving some overhang on the sides. This makes it easy to lift the brownies out later.

Step 2 | Prepare the Chocolate

Cut 105g of dark chocolate into larger chunks. Avoid chopping them too small—you want nice chocolate bites in your brownies. Place the chunks in a bowl and set aside.

Step 3 | Mix Dry Ingredients

Sift your flour and salt into the bowl with the chocolate chunks. This removes lumps and coats the chocolate evenly. Stir gently with a fork until everything is mixed.

Step 4 | Make the Chocolate Base

In a microwave-safe bowl, add butter, vegetable oil, cocoa powder, brown sugar, coffee powder, and vanilla extract. Stir lightly with a fork, then microwave for 20 seconds at a time, stirring after each interval. Continue until the mixture is melted and hot to touch—this usually takes about 1 minute.

Step 5 | Whip the Eggs and Sugar

In a separate bowl, combine white sugar and 2 eggs. Using a hand mixer, beat on medium-high speed for about 3 minutes until the mixture is light and creamy. This step helps create the signature crinkly brownie top.

Step 6 | Combine Wet Ingredients

Pour the hot chocolate mixture into the whipped eggs and sugar. Using a rubber spatula, gently fold until smooth and combined. Avoid overmixing at this stage.

Step 7 | Add the Flour Mixture

Add the flour and chocolate chunk mixture to the wet ingredients. Fold gently with a spatula until you no longer see dry flour. Be careful not to overmix—this keeps the brownies soft and fudgy.

Step 8 | Bake the Brownies

Pour the batter into the prepared tin. Give the tin a gentle shake to spread the batter evenly, then tap it lightly on the counter to release air bubbles. Bake for 22–25 minutes—for fudgier brownies, stick to 22 minutes; for a slightly firmer texture, bake for 25 minutes.

Step 9 | Cool and Cut

Allow the brownies to cool in the tin for at least 1 hour to firm up. Run a thin knife along the edges, then lift the brownies out using the baking paper. Slice into squares with a sharp knife and enjoy.

Brownie Baking Tips for Perfect Results

1. Measure Flour Correctly: Spoon flour into your measuring cup and level it off instead of scooping to avoid dense brownies.
2. Line Your Pan Well: Line your pan with baking paper to prevent sticking and make it easy to lift the brownies out.
3. Warm Your Knife: Warm your knife under hot water and wipe it clean between cuts for perfect brownie squares.
4. Check Doneness Properly: Insert a toothpick into the center—it should come out with a few moist crumbs for fudgy brownies.

Serving Ideas for Firehouse Subs Brownies

These brownies taste amazing on their own, but you can make them extra special! At Firehouse Subs, they serve their brownies warm with vanilla drink or a scoop of ice cream on top.

The cold ice cream melts slightly into the warm brownie – it’s perfect! You can also dust them with powdered sugar for a pretty look.

I love serving mine with fresh berries like strawberries or raspberries. The tart fruit goes perfectly with the rich chocolate.

For parties, I cut them into smaller pieces and put them on a nice plate.

Make Larger Batch for a Week

This recipe is perfect for making ahead when you want brownies all week long. I often double the recipe and use a 9×13 inch pan instead.

Just increase the baking time by about 5-8 minutes. The great thing about these brownies is they actually taste better the next day.

The flavors have time to develop and the texture becomes even more fudgy.

Brownie Storage & Freezing Tips

Store cooled brownies in an airtight container at room temperature for up to three days.

For best texture beyond that, store in the fridge. In the fridge brownies last up to one week. To freeze, wrap each brownie square tightly in plastic wrap.

Place wrapped pieces in a freezer bag and press out extra air before sealing. Label with date. Frozen brownies keep well for up to three months.

To thaw, move the wrapped piece to the fridge overnight. Warm in the microwave for 8–12 seconds to return to melty texture.

Reheat from frozen for about 20–25 seconds in the microwave, checking to avoid overheating.

When they show any weird smell, mold, or a slimy look, do not eat them.

A bad texture or off smell means they went off. For best taste, reheat just enough to warm; overheat will dry them out.

Firehouse Subs Brownie Recipe FAQs

1. How do I know when the brownies are done baking?

Insert a toothpick into the center. It should come out with a few moist crumbs, not wet batter. The top should look set and not jiggly when you gently shake the pan.

2. Why do my brownies turn out cakey instead of fudgy?

This usually happens when you overmix the batter or overbake them. Mix just until you can’t see any flour streaks, then stop. Also, check your baking time carefully.

3. Can I add nuts or other mix-ins?

Absolutely! You can fold in 1/2 cup of chopped walnuts, pecans, or chocolate chips with the flour mixture. Just make sure not to add more than 1/2 cup total or the batter will be too crowded. Mini marshmallows, dried fruit, or crushed cookies also work well. Add them at the same time as the flour.

4. Can I use an electric oven without a fan?

Yes. Set the oven to 170°C (338°F) for a non-fan oven. Fan ovens use lower temp because they circulate air. Use the center rack and check at about 20 minutes. Baking time can vary by oven so keep an eye on the center. A toothpick with moist crumbs is the right sign.

5. What if I don’t have a mixer?

No problem! Use a whisk and whip eggs/sugar for 5-6 minutes by hand. Get your arm ready—it should look thick and pale yellow. This step is key for crackly tops.