Preheat oven to 350°.
Grease a loaf pan with canola oil cooking spray.
Drain and rinse pinto beans in a strainer or sieve. Mash beans in a large bowl with a large spoon until there are no large pieces. Set aside.
Heat oil in a large skillet. Add onion and celery; sauté until onions are clear, about 10 minutes. Add sausage seasoning, stir until mixed. Remove from heat.
Add onion-celery mixture and breadcrumbs to the beans. Mix with your hands or a large spoon. Add ground pork and egg; mix well.
Scoop vegetable-meat mixture into loaf pan. Press down and smooth out the top.
Bake 1 hour or until internal temperature is 160°. Remove from oven; allow loaf to rest 5 to 10 minutes.
Remove loaf from pan and discard fat. Slice into 8 pieces.
Serve with mashed potatoes and sour cream, tomatoes and green salad.
Cool and refrigerate or freeze leftovers.