Quick Recipe Version (TL;DR)
Quick Ingredients
- Unsalted butter 1/2 cup (115 g)
- Bittersweet chocolate, chopped 4 oz (115 g)
- Granulated sugar 1 cup (200 g)
- Light brown sugar 1/4 cup (55 g) + 3/4 cup (150 g), divided
- Large eggs 2 + 1 large yolk
- Vanilla extract 2 tsp
- All-purpose flour 3/4 cup (95 g)
- Dutch-process cocoa powder 1/4 cup + 1/4 cup (50 g total), divided
- Espresso powder 3 tsp, divided
- Fine sea salt 1/2 tsp + pinch
- Hot brewed coffee 1 1/2 cups (355 ml)
- Optional: vanilla ice cream or lightly sweetened whipped cream
Do This
- 1. Heat oven to 350°F (175°C). Butter an 8-inch square or 2-qt baking dish.
- 2. Melt butter and chocolate until smooth; whisk in granulated sugar and 1/4 cup brown sugar.
- 3. Whisk in eggs and yolk, vanilla, and 2 tsp espresso powder. Fold in flour, 1/4 cup cocoa, and 1/2 tsp salt.
- 4. Spread batter in dish. Mix topping: 3/4 cup brown sugar, 1/4 cup cocoa, 1 tsp espresso powder, pinch salt; sprinkle over batter.
- 5. Gently pour hot coffee over the top. Do not stir.
- 6. Bake 28–35 minutes until top is set and crackly, center jiggles, and sauce bubbles at edges.
- 7. Rest 10 minutes. Scoop warm, spooning mocha sauce over. Serve with ice cream or whipped cream.
Why You’ll Love This Recipe
- Delivers a molten, mocha-fudge center with a crackly brownie top.
- Self-saucing magic: a quick topping transforms into glossy mocha pudding beneath.
- Big chocolate flavor boosted by espresso for true mocha depth.
- Simple pantry ingredients, no mixer required.
Grocery List
- Produce: Fresh raspberries and mint (optional, for serving)
- Dairy: Unsalted butter; large eggs; vanilla ice cream or heavy cream (optional)
- Pantry: Bittersweet chocolate; granulated sugar; light brown sugar; all-purpose flour; Dutch-process cocoa powder; espresso powder; vanilla extract; fine sea salt; coffee (for brewing)
Full Ingredients
For the Brownie Batter
- Unsalted butter 1/2 cup (115 g), plus extra for greasing
- Bittersweet chocolate (60–70%) 4 oz (115 g), finely chopped
- Granulated sugar 1 cup (200 g)
- Light brown sugar 1/4 cup (55 g), packed
- Large eggs 2, at room temperature
- Large egg yolk 1, at room temperature
- Vanilla extract 2 tsp
- Instant espresso powder 2 tsp
- All-purpose flour 3/4 cup (95 g)
- Dutch-process cocoa powder 1/4 cup (25 g)
- Fine sea salt 1/2 tsp
For the Mocha Self-Saucing Topping
- Light brown sugar 3/4 cup (150 g), packed
- Dutch-process cocoa powder 1/4 cup (25 g)
- Instant espresso powder 1 tsp
- Fine sea salt pinch (about 1/8 tsp)
- Hot brewed coffee 1 1/2 cups (355 ml), just off the boil
To Serve (Optional)
- Vanilla ice cream or softly whipped cream
- Dark chocolate shavings or a pinch of flaky sea salt
Step-by-Step Instructions
Step 1: Preheat and prepare the pan
Heat the oven to 350°F (175°C) with a rack in the center. Generously butter an 8-inch square baking dish (or any 2-quart/2-liter casserole). For extra-easy scooping, line with a parchment sling and butter the parchment.
Step 2: Melt the butter and chocolate
Place the butter and chopped bittersweet chocolate in a medium heatproof bowl. Microwave at 50% power in 30-second bursts, stirring each time, until smooth (about 1 1/2–2 minutes total). Alternatively, set the bowl over a pot of barely simmering water and stir until melted, then remove from heat.
Step 3: Build the brownie batter
Whisk the granulated sugar and 1/4 cup (55 g) brown sugar into the warm chocolate mixture. Whisk in the eggs and yolk, one at a time, until glossy and slightly thick, 30–45 seconds. Add vanilla and 2 tsp espresso powder; whisk to combine.
In a separate bowl, whisk the flour, 1/4 cup (25 g) cocoa, and 1/2 tsp salt. Using a spatula, fold the dry ingredients into the wet just until no dry streaks remain. Do not overmix.
Step 4: Pan the batter
Scrape the batter into the prepared dish and smooth the top with an offset spatula. Tap the dish once or twice on the counter to level.
Step 5: Mix the mocha topping
In a small bowl, combine 3/4 cup (150 g) brown sugar, 1/4 cup (25 g) cocoa, 1 tsp espresso powder, and a pinch of salt. Sprinkle this mixture evenly over the batter, covering it from edge to edge.
Step 6: Add hot coffee and bake
Slowly pour the hot brewed coffee (355 ml) over the entire surface. Pour gently to avoid creating craters; do not stir. The liquid will sink as it bakes and form a glossy mocha pudding beneath the brownie layer.
Bake for 28–35 minutes, until the top is set and crackly, edges look slightly dry, the center still jiggles, and you see bubbly mocha sauce at the sides. If using a glass dish, start checking at 28 minutes.
Step 7: Rest and serve warm
Let the pudding rest 10 minutes so the sauce thickens slightly. Scoop into bowls, spooning extra mocha sauce from the bottom over each portion. Serve with a small scoop of vanilla ice cream or a dollop of softly whipped cream. Finish with chocolate shavings or a pinch of flaky salt, if desired.
Pro Tips
- Dutch-process cocoa delivers a deep color and smooth chocolate flavor. Natural cocoa works, but the flavor will be lighter and a bit sharper.
- Use strong, freshly brewed coffee for the best mocha note; decaf is fine. For less sauce, use 1 1/4 cups (295 ml) coffee; for extra saucy, up to 1 3/4 cups (415 ml).
- Do not stir after pouring on the coffee. The contrast of dry topping and hot liquid is what creates the self-saucing layer.
- Chop the chocolate finely so it melts quickly and blends smoothly into the batter.
- Bake until the center wobbles but is not sloshy; pulling it early preserves the molten center, while overbaking dries the sauce.
Variations
- Boozy Mocha: Replace 2 tbsp (30 ml) of the hot coffee with coffee liqueur (Kahlúa) and add 1 tbsp (15 ml) liqueur to the batter.
- Salted Tahini Swirl: Dollop 2 tbsp (30 g) tahini over the batter in Step 4 and swirl lightly; finish with flaky sea salt.
- Gluten-Free: Swap the flour for a 1:1 gluten-free all-purpose blend (95 g). Bake as directed.
Storage & Make-Ahead
Leftovers keep, covered and refrigerated, for up to 3 days. Reheat individual portions in the microwave for 20–30 seconds, or warm the whole dish at 300°F (150°C) for 10–12 minutes. To prep ahead, mix the dry batter ingredients (flour, cocoa, salt) and the dry topping ingredients (brown sugar, cocoa, espresso, salt) up to 2 days in advance. You can also assemble the batter in the pan, cover, and refrigerate up to 24 hours; bring to room temperature for 30 minutes, add the topping and hot coffee, then bake.
Nutrition (per serving)
Approximate values: 460 calories; 23 g fat; 64 g carbohydrates; 6 g protein; 3 g fiber; 49 g sugars; 230 mg sodium.
