Ingredients

2 sticks (1 cup) salted butter

2 cups semi-sweet chocolate chips

1 cup granulated sugar

1 tablespoon hazelnut liqueur

2 teaspoons vanilla extract

4 large eggs, at room temperature

1/2 cup all-purpose flour

1/2 cup unsweetened cocoa powder

1 teaspoon baking powder

flaky sea salt

1-2 cups marshmallows

2 ounces dark chocolate chunks

Instructions

Step 1: Preheat the oven to 350°F. Line a 9×9 inch pan with parchment paper for easy removal.

Step 2: In the microwave, melt the butter and 1 1/2 cups of semi-sweet chocolate chips together until smooth. Stir in the sugar, hazelnut liqueur (if using), and vanilla extract.

Step 3: Whisk the eggs in a bowl for about 1 minute until bubbly on the surface. Incorporate the whisked eggs into the chocolate mixture.

Step 4: Add the flour, cocoa powder, baking powder, and a pinch of flaky sea salt. Stir just until combined, then fold in the remaining 1/2 cup chocolate chips.

Step 5: Spread half of the batter evenly into the prepared pan and bake for 20 minutes. Remove from the oven and switch the oven setting to broil.

Step 6: Arrange marshmallows evenly over the partially baked bars. Broil for 1 to 3 minutes, watching carefully, until the marshmallows are toasted to your preference.

Step 7: Lower the oven temperature back to 350°F. Spread the remaining batter over the toasted marshmallows, covering as much as possible. Press the dark chocolate chunks into the top.

Step 8: Bake for an additional 20 minutes until the top is set but the marshmallows underneath remain soft and wiggly.

Step 9: Let the bars rest in the pan for 20 minutes. Then lift them out using the parchment paper. Serve warm for a gooey experience or let cool before cutting and gifting.

Tips & Variations

For an extra nutty twist, add chopped toasted hazelnuts or walnuts to the batter before baking.

If you prefer a boozy kick, increase the hazelnut liqueur slightly or substitute with Irish cream.

Use mini marshmallows for a more even layer and quicker toasting under the broiler.

For a dairy-free option, substitute butter with coconut oil and use dairy-free chocolate chips.

FAQs

Can I skip the hazelnut liqueur?

Yes, the hazelnut liqueur adds a lovely depth of flavor, but the bars will still be delicious without it. You can replace it with a teaspoon of espresso powder or just omit it entirely.

How do I prevent marshmallows from burning under the broiler?

Keep a close eye on the marshmallows as they broil since they toast quickly. Broil in short bursts of 30 seconds to 1 minute, stopping as soon as they turn golden brown.