1 1/2 to 2 pounds not-too-lean sirloin, in chunks
1/2 white onion, peeled and in chunks, optional
Salt and pepper to taste

Start a charcoal or wood fire or preheat a gas grill. Or, on stove top, heat a large, heavy skillet over medium-high heat for 3 or 4 minutes.

Put meat and onion in a food processor, in batches if necessary, and pulse until coarsely ground: finer than chopped, but not much. Put it in a bowl and sprinkle with salt and pepper. Taste, then add more seasoning if necessary. (If desired, cook a teaspoon of meat in a pan before tasting.) Handling meat as little as possible to avoid compressing it, shape it lightly into 4 or more burgers.

Fire is hot enough when you can barely stand to hold your hand 3 or 4 inches over rack for a few seconds. Grill burgers about 3 minutes a side for very rare, and another minute a side for each increasing stage of doneness, but no more than 10 minutes total unless you like hockey pucks. (Timing on stove top is the same.)

Serve on buns, toast or hard rolls, garnished as you like.