4 tablespoons safflower oil
1 cup plus 2 tablespoons chopped onion (from 1 medium onion)
4 garlic cloves, minced
2 cans (15 1/2 ounces each) pinto beans, drained, liquid reserved
2 medium tomatoes, finely chopped
1/2 teaspoon coarse salt
2 ripe avocados, halved, pitted, and peeled
1 to 2 pickled jalapeno chiles, minced
1 cup plus 2 tablespoons sour cream
2 tablespoons fresh lemon juice
3 ounces cheddar cheese, grated (1 cup)
6 scallions, thinly sliced
6 ounces pitted black olives, chopped
1 to 2 bags tortilla chips, for serving