Preheat the oven to 350°F.
Add the white chocolate melting wafers and coconut oil to a microwave-safe bowl. Microwave in 30-second intervals, stirring between each, until melted and smooth.
Pour the chocolate mixture into the skull mold and tilt to swirl the chocolate around until coated entirely. Refrigerate until set for 30 minutes.
Whisk together the flour, baking powder, baking soda, and salt in a medium bowl.
Beat the butter in a large bowl with an electric mixer on medium speed until pale yellow. Add the confectioners' sugar and beat on low to combine, then beat on high until light and fluffy.
Scrape down the sides of the bowl and add 1 tablespoon vanilla and the egg, mix to combine. Gradually add the flour mixture & mix on low speed.
Divide batter into the prepared cupcake pan. Bake 35 minutes & transfer to a rack to cool.
Ice cupcakes and position the skull in the center.
Set aside ¼ cup of strawberries for garnish. Add the remaining strawberries & granulated sugar to a small saucepan over medium heat. Cook, stirring occasionally, until mixture has thickened. Remove from the heat and stir in lemon juice & remaining vanilla.
When ready to serve, pour the strawberry sauce over the center of the chocolate skull and garnish with berry slices.
For even more impact, add desired food coloring to icing.