Heat a large nonstick skillet over medium-high heat. Sprinkle pork with salt and black pepper. Add oil to pan. Add pork, and sauté 4 minutes or until browned. Remove pork from pan; place in a bowl. Add onion and jalapeño to pan; sauté 5 minutes or until tender. Add broth; reduce heat, and simmer 1 minute, scraping pan to loosen browned bits. Stir in tomato; simmer 2 minutes.