Pierce potatoes with a fork. Cook in a microwave oven on full power (100%), turning over once, until potatoes are tender when pierced, 15 to 20 minutes. Or bake in a conventional oven at 400 until tender when pierced, about 45 to 55 minutes.
Meanwhile, in a 10- to 12-inch nonstick frying pan over high heat, stir beef until crumbled and lightly browned, about 5 minutes.
Add chili powder to beef and stir about 1 minute.
Add tomato sauce and salsa. Reduce heat and simmer, uncovered, to blend flavors, about 5 minutes.
Cut the potatoes in half lengthwise. Spoon meat mixture equally onto cut side of each potato half, and top equally with cheese, tomato, onions, and olives.
