Combine meat and pepper in a small Dutch oven coated with cooking spray. Cook over medium-high heat 10 minutes or until browned, stirring to crumble. Drain, if necessary.
Reduce heat to medium; add corn, and cook, uncovered, 3 minutes, stirring occasionally. Add diced tomatoes and salsa; cook, uncovered, 5 minutes, stirring occasionally. Ladle into each of 4 soup bowls. Top each serving with 3 tablespoons cheese and, if desired, pumpkinseeds.