In a medium bowl, sift together flour, cocoa powder, sugar, baking powder and salt. Set aside.
In a mixing bowl with whisk attachment, or using an handheld electric mixer,or by hand, beat the eggs for a minute. Stir in milk and vanilla extract. Add the flour mixture and beat on medium low speed just until combined, 1-2 minutes. Don’t overmix, or the batter will get tough and rubbery! Cover the mixture with a plastic wrap, so that it touches the surface of the batter. Let it rest for at least 30 minutes. When ready to fry the crepes, whisk in the vegetable oil.
Heat 10-inch non-stick skillet over medium high heat. (The bottom of my 10-inch pan measures 7 inches, which means the crepes will be 7-inch round.) Place a little less than ¼ cup of batter into the hot pan, quickly swirl the pan so the batter is evenly covers the bottom of the pan. In about 1 minute, when the edges of the crepe start to pull away, flip it over using a spatula. Cook for about 30 seconds or so and stack the crepes on a plate. You’ll get about 20 crepes. Cool the crepes completely. You can wrap the crepes with a plastic wrap and refrigerate for up to a day.
To make the mousse filling, dissolve the cocoa powder in ¼ cup (60ml) hot water. Set aside.
In a double boiler, melt chocolate chips until smooth. Remove from heat and cool slightly. Stir in the cocoa mixture.
In a mixing bowl with whisk attachment, whip the heavy cream until hard peaks form. Fold in the whipped cream into the melted chocolate and gently mix until no white streaks remain.
Spread heaping one tablespoon of mousse filling on a crepe. Place another crepe on top and spread another heaping tablespoon of mousse filling. Repeat until all crepes are used. Store in airtight container in the fridge until ready to serve. Top the cake with pomegranate seeds and dust some powdered sugar generously using a mesh sieve right before serving.
For step-by-step photos and additional notes, read the post above.