Season venison with salt, pepper and garlic powder to taste. Saute onion in a large frypan; when soft, add venison and brown. Drain when venison is no longer pink then add soup. Reduce heat to low and simmer.
Meanwhile, bring a large saucepan of lightly salted water to a boil. Add egg noodles then cook for 8 to 10 minutes or until al dente; drain.
When egg noodles are almost done cooking, stir sour cream into meat mixture. Pour meat mixture over hot cooked egg noodles and serve.