Double Chocolate Layer Cake

This is my go-to chocolate cake. It's simply excellent: moist with deep, rich flavor. I like my chocolate mascarpone frosting on it, although a chocolate espresso buttercream is good too. The recipe makes a tall cake, so please don't try to put all the batter in two 9" pans; make a few cupcakes too.

3 ozs semisweet chocolate chips (I like Ghirardelli)
1 1/2 c hot brewed coffee
3 c sugar
2 1/2 c all-purpose flour
1 1/2 c unsweetened natural (not Dutch process) cocoa powder
2 tsp baking soda
3/4 tsp baking powder
1 1/4 tsp salt
3 large eggs
3/4 c vegetable oil
1 1/2 c buttermilk
3/4 tsp vanilla extract

Preheat oven to 300°F. Grease two 10" pans with shortening; line bottoms with rounds of parchment paper, then grease paper.

Place chocolate chips in a small bowl. Pour coffee over; let mixture stand, stirring occasionally, until chocolate is melted and mixture is smooth. 

Sift sugar, flour, cocoa powder, baking soda, baking powder, and salt into a large bowl. In a pitcher with a spout, stir together oil, buttermilk and vanilla.

In the work bowl of a stand mixer, beat eggs on medium-high speed until lemon-yellow and slightly thickened, about 3 minutes. Drizzle in oil, buttermilk, vanilla, and melted chocolate mixture to eggs, beating until combined well. Add sugar-flour mixture; beat on medium speed until just combined well. 

Divide batter between pans; bake in middle of oven until tester inserted in center comes out clean, 60 to 70 minutes. Cool layers completely in pans on racks. Run a thin knife around edges of pans; invert layers onto racks. Carefully remove paper. Fill and frost as desired.