Preheat the oven to 350℉.

Combine the all-purpose flour, coconut flakes, baking powder, salt, and sugar in a large mixing bowl.

Slowly add in the melted vegan butter, vegetable oil, and 4 tablespoons of plant milk along with the vanilla extract.

Mix with a spatula until the dough becomes a glossy, cohesive mass.

Scoop dough using a 2-ounce scoop, forming round shapes.

Place on a parchment-lined baking sheet with 2 inches of space in between.

Bake for 15 minutes, then gently press a tablespoon into the center of each cookie to create an indent.

Return to the oven for an extra 3 minutes, then let cool completely on a wire rack.

Whisk together sugar and cornstarch in a small saucepan.

Gradually mix in the half cup of plant milk over medium heat.

Stir continuously until the mixture reaches a gentle boil, then remove from heat.

Whisk until it reaches a thick pudding-like consistency, then spoon the hot custard into the indents of cooled cookies.

Whip up your buttercream according to your favorite recipe, using only half for this project.

Once custard has cooled and set, pipe buttercream on top and sprinkle with toasted flaked coconut.