Using a cookie cutter, enlarge the centre of each bagel half to form a hole about 5 cm in diameter.
Brush the bagel with olive oil.
Heat the pan over a medium heat and wait until the Thermal-Signal has turned completely red before adding your ingredients.
Place the 4 slices in the pan and cook for 2 minutes per side. Break an egg in the centre of each slice. Season with salt and pepper. Sprinkle with cheese and chopped onion.
Cook over a low heat for 8 minutes. Turn the slices over gently and cook for 1 minute over medium heat to allow the white to finish cooking.