Heat oven to 450°F. Spray 15x10x1-inch pan with cooking spray. Spread cut-up fresh vegetables evenly in pan (pan will be full). In small bowl, mix oil and garlic; drizzle evenly over vegetables.
Bake 20 to 25 minutes, turning vegetables occasionally, until tender and beginning to brown. Cool 5 minutes.
In 3-quart Dutch oven or casserole, mix tomatoes, chili powder, cumin and garlic salt. Coarsely chop all roasted vegetables; stir into tomato mixture.
Reduce oven temperature to 375°F. Bake 40 to 50 minutes or until mixture is hot and bubbly.