Homemade Guacamole Recipe

1/4 cup finely minced onion

3 ripe Haas avocados

1 1/2 tablespoons fresh lime juice (or lemon juice)

1 large Plum or Roma tomato, deseeded and diced

1/4 cup cilantro leaves and tender stems, chopped

1/2 teaspoon ground cumin, optional

1/2 teaspoon salt, or more to taste

1 to 2 teaspoons minced jalapeño or serrano pepper, with seeds and membrane removed, optional