Pre heat your oven to 180C Fan/400F/Gas Mark 6
Put a frying pan on a low-medium heat and add the vegetable oil and let it warm up for a few minutes
Add the onion, pepper and garlic into the pan and cook the vegetables until soft. (If you are using any root vegetables instead, you will need to boil, steam or roast them until soft instead)
Remove the vegetables from the heat and set aside
Butter the slices of bread and cut them in half, then arrange them in your baking dish
In a large mixing bowl, add the eggs, milk, double cream, mixed herbs and salt. Whisk them together
Add the cooked vegetables all around and in between the slices of bread
Then pour the egg mixture all over and between the slices of bread
Add the cherry tomatoes all over and between the slices of bread (the tomatoes don't need cooking first)
Then cover the bread and vegetables with the grated cheese
Bake for 20-25 minutes until golden, bubbling and all the cheese is melted
Serve immediately with some fresh green veg or salad. Store leftovers in the fridge and eat within 2 days