Preheat oven to 350°.
To prepare salsa, combine first 8 ingredients in a small bowl. Cover and refrigerate.
To prepare beef, sprinkle beef with 1/2 teaspoon salt and 1/4 teaspoon pepper. Heat a Dutch oven over medium-high heat. Coat pan with cooking spray. Add beef; cook 5 minutes or until browned. Remove from pan.
Add 1 teaspoon oil and onion to pan. Reduce heat, and cook 12 minutes or until golden brown, stirring occasionally.
Return beef to pan. Add broth and beer; bring to a boil. Cover, reduce heat, and simmer 1 hour and 30 minutes or until tender. Remove beef from pan; shred with 2 forks. Return beef to pan; stir. Spoon 1/4 cup beef mixture over each bread slice; top each with 1 1/2 tablespoons salsa.