Heat the oven to 350°F. Spritz a 12-cup muffin tin with non-stick spray and set aside. Using a 3-inch biscuit cutter, remove circles of deli meat from the larger slices. Reserve the scraps for another use. Depending on the shape of the deli meat, you may need an additional slice or two. Using your fingertips, gently press the meat down into the prepared muffin tin. (It may tear a bit, but don’t worry. As long as it’s mostly intact you’ll be good to go.)
Heat the bacon in the skillet over medium heat and cook until the bacon is crispy and the fat has rendered, about 7minutes. Remove to a plate lined with paper towels. Pour off the bacon fat so that only a sheen remains in the pan.
Add the onion and cook, stirring occasionally, until golden brown, about 10 minutes. Add the flour. Stir to combine. The mixture will be dry. Whisk in the milk until no flour lumps appear. Remove from the heat. Add half of the cheese and stir to combine. Whisk in the egg, parsley, and spices. (You will have about 1 cup of sauce filling.)
Using a 1 tablespoon measuring spoon or scoop, fill the prepared turkey cups. Top with remaining cheese. Transfer to the oven and bake until puffed and set, about 10 minutes. Remove to a rack to cool slightly. Garnish with parsley leaves and serve.