Preheat your oven to 190°C (fan-forced) and line a 28 x 18cm slice tin with baking paper.
Roughly chop the tomato and ham into pieces and set aside until needed.
Place the cheese pieces into your Thermomix bowl and blitz for 10 seconds, speed 8 to grate.
Scrape down the base and sides of your Thermomix bowl and add the olive oil, garlic powder, onion flakes and self-raising flour and eggs and mix for 15 seconds, speed 5.
Add the ham and tomato pieces and mix for 10 seconds, speed 4 REVERSE.
Transfer the mixture into your prepared tin and gently smooth the surface. You can also sprinkle a little extra grated cheese over the top of the slice if you like.
Bake for 25 – 28 minutes or until golden on top and cooked through when tested with a skewer. Let the Ham, Cheese and Tomato Slice cool in the tin for 10 minutes before carefully transferring to a wire rack to cool completely.