This Chocolate Frozen Yogurt Brownie Cake is so divine with a rich, fudgy brownie base, homemade chocolate frozen yogurt and silky smooth dark chocolate ganache on top. It is incredibly easy to make as the frozen yogurt has just 2 ingredients and it's perfect for Summer.
Preheat the oven to 350°F. Line an 8.5x4.5-inch loaf pan with parchment paper so there is an overhang on each side for easy removal.
Make the brownie base. Melt together chocolate and butter in the microwave in short bursts with frequent stirring until completely melted, smooth and glossy. Crack in the egg and pour the sugar right over top of the egg. There’s no need to let the chocolate mixture cool before this step. Whisk well until evenly combined smooth and glossy. The mixture will look stiff and separated at first, but keep whisking and it will bind together, tighten up and look glossy as the sugar dissolves and the ingredients emulsify.
Sprinkle in flour, then sprinkle the baking powder and salt evenly over the flour. Fold it in until well incorporated and smooth. Spread batter into prepared pan and bake for 15-20 minutes until a skewer inserted into the center comes out with a few moist crumbs attached. Set it aside to cool completely.
Make the frozen yogurt. Combine chopped milk chocolate with hot water and place in the microwave for 45 seconds until the water starts to bubble a bit and it is hot. Do not let it boil, it just just start to make bubbles around the edges. Whisk until smooth and glossy.
Add the yogurt (cold is fine) and whisk gently until smooth and evenly combined. Mix in a pinch of salt. Pour the mixture over the cooled brownie and smooth it out. Tap the pan on the counter to let any large air bubbles burst at the surface, cover tightly with aluminum foil and then place in the freezer for at least 4 hours or overnight.
Make ganache. Combine semisweet chocolate with water in a heatproof bowl or jug and place in the microwave for 30-45 seconds until the water starts to bubble a bit and it is hot. Do not let it boil, it just just start to make bubbles around the edges. Whisk until smooth and glossy.
Cover with ganache. Once frozen, remove from freezer and run the bottom and sides of the pan under warm water to release the cake. Use the parchment overhang to lift it out of the pan and then run an offset spatula along the bottom to release the brownie from the parchment paper. Transfer it to a board or a serving plate. Pour ganache evenly over the top and quickly spread it out before it sets. After about 15 minutes, it should be soft enough so you can slice cleanly through the brownie. Slice with a hot dry knife like you would slice brownies. Serve with fresh berries and enjoy!
Keep this cake covered with plastic wrap, then aluminum foil and store it in the freezer for up to 1 month.