For the toasts with ham, cheese and egg on lettuce spread the toast slices with butter.
Chop the onion and hard-boiled eggs, cut the ham into small cubes and mix everything with the grated cheese.
Spread the mixture on the toast, season with salt, pepper and paprika powder to taste. Grill in the oven until the toast is crispy.
Arrange the lettuce leaves on a plate, place the toast slices on top, garnish with the cocktail tomatoes and serve the toasts with ham, cheese and egg on lettuce leaves.