While making chocolate ganache to frost some cakes the other day, I decided to replace half the sugar in the original recipe with mashed banana, adding it to the heavy cream as it came to a boil. Banana ganache turned out to be a versatile invention. With one batch, I was able to frost a few mini banana hazelnut brownie cakes, shape some truffles, and assemble shortbread ganache sandwich cookies – my absolute favorite of the three desserts. Creamy and smooth, with a mousse-like texture and the flavor of banana pudding, the ganache contrasts perfectly with crisp, buttery shortbread.
Chocolate Banana Sandwich Cookies
2 cups heavy cream
1/4 cup powdered sugar
1/8 teaspoon salt
1 pound dark chocolate, roughly chopped
1 banana, mashed
2 sticks (1 cup) unsalted butter, softened at room temperature
3/4 cup powdered sugar
1/2 teaspoon salt
2 cups all-purpose flour
Prepare the ganache: Combine heavy cream, sugar, salt, and mashed banana in a large saucepan, and bring to a boil. Remove from heat, and add chocolate. Let stand for a few minutes without mixing, then whisk until smooth. Let cool and refrigerate for at least an hour, until the ganache thickens and is easy to spread.
Prepare the shortbread cookies: Preheat oven to 375 degrees F and line a baking sheet with parchment paper or silicone mat. In a large bowl, cream together butter and sugar until light and fluffy. Add salt and then flour, stirring until just combined. On a very lightly floured surface, roll out until around 1/8-1/4 inch thick. If dough is too sticky, refrigerate first. Shape with round cookie cutters (I made some large, some small, and baked them in 2 batches.) Bake for around 10 minutes, until edges turn golden brown; adjust depending on the size of the cookies.
Assemble: Let shortbread cookies cool directly on the baking pan. Spread half the cookies with ganache, then cover with remaining cookies to form sandwiches. Or make open-faced sandwiches, and frost all the cookies with ganache. To store, refrigerate in an airtight container. Shape any leftover ganache into balls and roll in cocoa powder to form truffles, or use to frost a cake.
Yields approximately 16 two-inch cookies. Yield will vary depending on size.