Melt butter in a saucepan over medium heat. Cook and stir onion in melted butter until softened, 7 to 10 minutes.
Bring a large pot of lightly salted water to a boil. Cook egg noodles in the boiling water, stirring occasionally until cooked through but firm to the bite, about 5 minutes. Drain and return to the pot.
Stir butter and onion mixture, cottage cheese, sour cream, sea salt, and black pepper into the noodles. Place the pot over medium heat; cook and stir until heated through and warm, 5 to 8 minutes.
recipepes.comPolish Noodles (Cottage Cheese and Noodles), recipePT15MPT1H5455 calories