https://cooking.nytimes.com/recipes/1017505-egg-in-a-hole
Use a 2-inch cookie cutter to cut a hole in the middle of bread. Reserve the removed portion to toast, if desired. Break egg into a teacup.
Heat a heavy cast-iron skillet over medium-high heat, or over a medium-hot grill, for about 2 minutes. Add butter. When butter stops foaming, place bread in pan and reduce heat to medium. Cook 3 minutes and flip over. Gently tip egg into hole.
Sprinkle salt and pepper over egg and cook 3 minutes. Carefully flip egg and bread over, and cook for another 30 to 40 seconds, until egg is cooked just over-easy. Transfer to a plate and serve.