3 mocha walnut espresso coffee cake Recipes

all-purpose flour, ground walnuts, baking powder, salt, unsalted butter, at room temperature (8 oz), unsalted butter, at room temperature (1 oz), bittersweet chocolate, coarsely chopped, hot or cold coffee (can also use plain water), ground instant coffee or 1 tsp instant espresso powder, sugar, eggs, preferably at room temperature, pure vanilla extract, whole milk, at room temperature

flour, baking powder, salt, sugar, unsweetened cocoa powder, walnuts, coarsely chopped, milk (whole or low-fat ), unsalted butter, semisweet chocolate, coarsely chopped, vanilla extract, egg, lightly beaten, sugar, light brown sugar, unsweetened cocoa powder, brewed coffee (for a less-pronounced coffee flavor, may substitute 1 1/2 cups water plus 1 tsp espresso powder)