Chef Ron’s holiday Gumbo

8 tbsp. Oil/butter
1/2 c. all-purpose flour
2 small yellow onion
3 medium green bell pepper, chopped
4 celery ribs, finely chopped
4 cloves garlic, minced
16 oz. andouille sausage, sliced
3 tbsp. Cajun seasoning
Salt & black pepper
3 bay leaf
8 c. Seasoned stock
1 lb. medium shrimp, peeled and deveined
3 green onions, sliced
Louisiana hot sauce