Preheat the oven to 350°F (177°C). Line a 12-cup muffin pan with cupcake liners.

Whisk the flour, cocoa powder, baking soda, baking powder, and salt together in a large bowl. Set aside.

Whisk the oil, sugar, egg, vanilla, and buttermilk together until combined. Pour the wet ingredients into the dry ingredients, add the hot coffee/water, and whisk until the batter is completely combined.

Pour/spoon the batter into the liners, filling only ⅔ full. Bake for 20–22 minutes, until a toothpick inserted comes out clean.

Allow cupcakes to cool for 10 minutes, then transfer to a wire rack to cool completely.

For the ganache, place chocolate in a heatproof bowl. Heat the cream until it begins to simmer, then pour it over the chocolate. Let sit for 2–3 minutes, then stir until smooth. Chill in the refrigerator for at least 30 minutes.

For the strawberry buttercream, process the freeze-dried strawberries into a powder. Beat the butter until creamy, then add the sugar, strawberry powder, heavy cream, and vanilla. Beat until well combined.

Cut a circle into the center of each cooled cupcake to create a pocket. Fill with strawberry buttercream.

Spread the chilled chocolate ganache on top of each cupcake. Garnish with fresh strawberry slices or sprinkles, if desired.

Serve immediately or store covered at room temperature or in the refrigerator for up to 1 day.