This old-fashioned Coconut Sheet Cake is a quick and easy cake with a delicate coconut flavor in both the cake and the whipped frosting. Add toasted coconut on top for a simple finish.
Preheat the oven to 350°F (175°C). Line a 9" x 13" x 2" baking pan with parchment paper. Lightly grease the paper and any exposed parts of the pan. (Or grease the pan if you don't want to line it.)
Whisk together the flour, baking powder, baking soda, and salt. Set aside.
Using an electric mixer on medium speed, beat the butter and sugar until light and fluffy. Add the eggs, one at a time, mixing well after each addition. Mix in the vanilla.
Reduce the mixer speed to low. Add the flour in three portions, alternating with two portions of coconut milk. Mix just until combined.
Transfer the batter to the prepared pan, and spread evenly. Gently tap the pan on the countertop a few times to displace any large air pockets.
Bake the cake for 35 to 40 minutes, or until the cake is golden brown and a pick inserted into the center comes out clean.
Place the pan on a wire rack and cool completely.
To make the whipped cream:
Place the cold heavy cream and coconut milk in a large, chilled mixing bowl. Use an electric mixer with a whisk attachment to whip the cream. Start on low speed and work up to high speed over about a minute.
When the cream begins to thicken, sprinkle as much of the sugar as you like on top of the cream. Continue whisking until stiff peaks form.
Spread the whipped cream over the top of the cooled cake. Sprinkle the coconut over the top, and gently press down so that the coconut sticks to the whipped cream.
Notes
Be sure to use canned coconut milk, not coconut milk in a carton that has been diluted to a drinkable consistency.