If memory serves my Mom made sweedish meatballs with sauce using sour cream. YUM! Here are the ingredients at one site:

https://www.ruled.me/keto-swedish-meatballs/

Swedish Meatballs

1-pound ground beef
1 tablespoon dried parsley
¼ teaspoon allspice
¼ teaspoon nutmeg
½ teaspoon garlic powder
Salt and pepper, to taste
¼ onion, diced
2 tablespoons butter

Beef Gravy

4 tablespoons butter
1½ cups beef stock
½ cup heavy whipping cream
½ cup sour cream
2 tablespoons Worcestershire sauce
½ tablespoon Dijon mustard
Salt and pepper, to taste
1 teaspoon xanthan gum