Preheat oven to 350°F. Mix chicken, cheese, tomato, green onions, chili powder, cumin, garlic salt and oregano.
Place 4 of the tortillas on ungreased baking sheet. Spread 1/4 of the chicken mixture evenly on each tortilla. Top with remaining tortillas. Lightly brush with oil.
Bake 5 to 10 minutes or just until cheese is melted. Cut into 3-inch wedges. Serve warm.