In a large frying pan, saute the onion and garlic in olive oil. Set aside.
Brown the pork in the same pan just until it is no longer pink. Add the onion and garlic mixture and season with salt and pepper to taste. Cover and cook 5 minutes.
Add the green, red, and yellow peppers, and raisins. Mix well, cover and cook for another 5 minutes.
Add the spinach. Mix well and serve hot with bread or rice.