Pizza toast

2 slices bread (or a bagel or a
piece of French stick sliced in half)
½ pepper
1 spring onion or a small onion
1 mushroom
30g hard cheese, e.g. Cheddar,
Edam, Gruyere
2 x 15ml spoons tomato puree or tomato ketchup
½ x 5ml spoon mixed herbs (optional)