For the Cupcakes:

1. Preheat the oven to 350°F (175°C) and line a muffin tin with cupcake liners.
2. In a bowl, whisk together the flour, sugar, baking soda, cocoa powder, and salt.
3. In another bowl, mix together the oil, buttermilk, eggs, vanilla, vinegar, and red food coloring.
4. Gradually mix the wet ingredients into the dry ingredients until smooth.

For the Cheesecake Filling:

1. Beat the cream cheese, sugar, vanilla, and egg until smooth. Fold in the diced strawberries.

Assemble the Cupcakes:

1. Fill the cupcake liners halfway with the red velvet cupcake batter.
2. Add a spoonful of the cheesecake filling into the center of each cupcake.
3. Top with more batter to cover the cheesecake filling.
4. Bake for 18-22 minutes, or until a toothpick inserted into the center comes out clean. Let cool completely.

For the Frosting:

1. Beat the cream cheese and butter together until smooth.
2. Gradually add the powdered sugar and vanilla extract, mixing until fluffy.

Decorate:

1. Pipe the frosting onto the cooled cupcakes.
2. Garnish with fresh strawberry slices and red velvet crumbs for an extra touch of color and flavor.