Preheat the oven to 200°C.
Lightly grease a muffin tin or put 6 silicon muffin cases on a baking tray.
Line each hole with a slice of bacon, then put a couple of tomatoes in the middle.
Bake in the oven for 5 minutes.
Meanwhile lightly whisk the eggs. Add most of the grated cheese, if used.
Take the tin out of the oven and divide the egg mixture between the cups.
Scatter some cheese on top, season with pepper and put one tomato piece on top of each.
Turn down the oven temperature to 180C and bake the muffins for 20-25 minutes until golden. (You can brown the top with a blow torch or under the grill, if preferred.)
Serve immediately or let them cool.