8 ounces sharp Cheddar, cut into 1/2-inch cubes
3 tablespoons lager beer
1 tablespoon vegetable oil
1/2 teaspoon Dijon mustard
1/2 teaspoon Worcestershire
1/8 teaspoon cayenne
1 1/2 cups all-purpose flour, plus more for dusting
1 1/2 teaspoons baking powder
1/2 teaspoon kosher salt
4 tablespoons cold unsalted butter, cut into cubes, plus 2 tablespoons, melted
1/2 cup buttermilk
3 slices Black Forest ham, halved
1 scallion, thinly sliced