Thanks for the prompt response. Here’s the recipe. It’s from Cooks Illustrated back in 2000 before they used measuring by weight in their recipes. Now their standard weight measurements are 5 oz. for unbleached AP flour and 4 oz. for cake flour per cup. My butter and eggs are at 68 degrees.
4ounces unsweetened chocolate, chopped
¼cup Dutch-processed cocoa powder
1 ¼cups water (boiling)
¾cup unbleached all-purpose flour
¾cup cake flour
1teaspoon baking soda
¼teaspoon table salt
8ounces unsalted butter (2 sticks), softened, plus extra for greasing pans
1 ½cups packed dark brown sugar
3 large eggs, room temperature
½cup sour cream
1teaspoon vanilla extract
Makes three 8-inch cakes
Regular, or natural, cocoa like Hershey’s can be used with good results, though the cakes will bake up a bit drier, redder, and with slightly less chocolate flavor.
1. Adjust oven rack to upper- and lower-middle positions; heat oven to 350 degrees. Meanwhile, grease three 8-inch cake pans with butter and line bottom of each pan with parchment paper round. Combine chocolate and cocoa in medium bowl; pour boiling water over and whisk until smooth. Sift together flours, baking soda, and salt onto large sheet parchment or waxed paper; set aside.
2. Place butter in bowl of standing mixer and beat at medium-high speed until creamy, about 1 minute. Add brown sugar and beat on high until light and fluffy, about 3 minutes. Stop mixer and scrape down bowl with rubber spatula. Increase speed to medium-high and add eggs one at a time, beating 30 seconds after each addition. Reduce speed to medium; add sour cream and vanilla and beat until combined, about 10 seconds. Stop mixer and scrape down bowl. With mixer on low, add about one third of flour mixture, followed by about one half of chocolate mixture. Repeat, ending with flour mixture; beat until just combined, about 15 seconds. Do not overbeat. Remove bowl from mixer; scrape bottom and sides of bowl with rubber spatula and mix gently to thoroughly combine.
3. Divide batter evenly among cake pans, smooth batter to edges of pan with rubber spatula. If baking three 8-inch cakes, place two pans on lower-middle rack and one on upper-middle rack. Bake until skewer inserted in center comes out clean, 20 to 23 minutes for 8-inch cakes. Cool on wire rack 15 to 20 minutes. Run knife around pan perimeter to loosen. Invert cakes onto large plate; peel off parchment, and reinvert onto lightly greased rack. Cool completely before icing.