Too much red cabbage leftover!

Red Flannel Hash...Brown some ground beef in a skillet with garlic and onion, grate a cooked red beet (or several) and saute it with the cabbage. Add salt, pepper and dill. Serve with sour cream.

Ah, Marcella Hazan's Smothered Cabbage is pretty damn scalable, and pretty damn good:

https://www.google.com/search?q=marcella+hazan+braised+cabbage&rlz=1C5CHFA_enUS843US843&oq=marcella+hazan+braised+cabb&aqs=chrome.0.0i512j69i57.15372j0j4&sourceid=chrome&ie=UTF-8

You can also find her smothered cabbage with rice on Food52 . . .

Make chow fun! Thinly sliced cabbage, bean sprouts, lunes from half an onion, and a couple of celery stalks sliced up can be used to begin a stir-fry for any meat, sauteed up with garlic and ginger. Add soy sauce and serve with chopped cilantro leaves. Pork chop meat sliced up thin is delicious to use with this.

Braised cabbage is a winter staple in my kitchen when other vegetables aren't at their best.
Chop the cabbage; melt butter in a saute pan; throw in cabbage, salt, pepper, thyme, and a little water. Cook and stir over medium heat until it's wilted.

Fried Cabbage w/Bacon: 6 slices bacon (I cheat and use bacon bits), 1 lg onion slices, 2 tsp sea salt, 1 medium cabbage thinly slices (any color), 2 tsp freshly ground black pepper, 4-6 tbsp apple cide vinegar. Cook bacon in dutch oven or large cast iron skillet until done with plently of bacon grease in the skillet. Remove bacon and set aside. Cook onions in bacon grease, then add salt/pepper and sliced cabbage. Stir well and continue to cook on medium high heat stirring often to cook cabbage (15-20 Min). Remove cabbage from heat and stir in vinegar and chopped bacon

Years ago I was given a recipe for something called Indonesian noodles. Very adaptable. Shred cabbage. Cook until soft with sliced onions. Cook wide noodles. Combine noodles and cabbage mixture and add medium sweet soy sauce. Done ✔️ Can add cooked meat to make it a full meal.

I love this cabbage and rice pilaf. You can easily double the cabbage.
https://unwrittenrecipes.com/blog/2017/small-victories-best-rice-pilaf-with-roasted-red-cabbage-famous-fridays

You can use your leftover cabbage in making fried rice -- a great way to use up leftover rice along with odds and ends of vegetables. Here is a Food52 recipe for fried rice with some cabbage in it: https://food52.com/recipes/66947-stir-fried-rice-with-leftovers

There is a Food52 recipe for crispy sheet pan rice, here, https://food52.com/blog/23455-easy-dinner-recipes-best-rice-recipe-with-bacon-fast, that uses cabbage. (Basically a baked sheet pan version of fried rice that you can put your leftover cabbage into, using rice and whatever vegetables that you want.)

In addition to Miss_Karen's ideas, 3 more for what to do with the extra cabbage you have now:
1) Simply saute some or all. This will reduce volume and increase flavor. Then freeze in usable portions for future dishes (freezes well).
2) Sauté grain, cabbage & onions in butter or other flavorful fat. With buckwheat, this is called Kasha Varnishkes. I forget what it's called when you use short pasta. All are delicious. Eat as is, or add garnishes to taste - sour cream, poached egg, a bit of leftover meat.
3) Make soup. Many varieties and co-conspirators work well with the cabbage - beets, potatoes, fish.

Most grocery stores will cut the head of cabbage in half for you if you ask. I mix about a handful into my chicken wild rice soup. Saute it with the onions and celery. Then puree it before you add the chicken & rice. I also use some in my Oriental meatballs. (You can make the meatballs and then freeze them...) you might consider getting a bagged version of shredded cabbage it's a smaller quantity.