Mix the flour, baking powder, salt and a little of the milk to a smooth paste. Gradually add the remaining milk while whisking. Add the egg, beating the mixture well. For a lighter texture, leave to rest for a few hours or overnight.
Melt the butter and oil in a large frying pan and wait until it sizzles. Pour in enough of the mixture to cover the entire surface of the pan (spread the mixture evenly by tilting the pan). Bake until bubbles appear on the surface and turn over. Pancakes should be pale gold on both sides. Set aside.
Fry bacon in the pan until crisp and/or cooked. Remove to a paper towel to drain. Now add the sliced apples to the bacon fat and caramelize. Drain on paper towels. Serve pancakes open-faced on the plate, top with apples and bacon and drizzle some maple syrup on top.