Slow Cooker Belgian Chicken Booyah

4 pounds skinless

boneless chicken thighs

cut into 1-inch pieces

2 pounds red potatoes

cut in 1-inch pieces

1 pound beef stew meat

cut into bite-size pieces

1 (16 ounce) package frozen whole kernel corn

1 (16 ounce) package frozen cut carrots

1 (15 ounce) can cut green beans

drained

1 (14.5 ounce) can chicken broth

8 ounces diced celery

1 (14.5 ounce) can beef broth

1 (14.5 ounce) can petite diced tomatoes

8 ounces diced onion

8 ounces diced green bell pepper

8 ounces cabbage

shredded

¼ cup salt

or to taste

2 tablespoons dried basil

2 tablespoons dried oregano

2 tablespoons celery salt

1 tablespoon ground black pepper

1 0.42 oz packet concentrated vegetable base (such as Swanson® Vegetable Flavor Boost®)