Swedish meatballs

Christmas is approaching, and even at such a holiday, I prefer to stick to LCHF.
Therefore I make my own meatballs. Without sugar, gluten or other unnecessary ingredients.
Here is an updated recipes with a little more precise measure than the original recipe.
If you try my recipe feel free to comment what you think. If you upload a picture on Instagram or other social medias: tag me so I can see your results :-)
50 meatballs:
500g minced beef (ground beef or mixed mince, both work)
1/2 yellow onion, grated or finely chopped
1 egg
1/2 cup heavy cream
1 teaspoon salt
1 pinch of pepper

Do this:
Finely chop or grate the onion.
Mix meat, onion, cream, eggs and spices by hand in a bowl.
Roll into bite-sized rolls and place them on a baking tray with baking paper.
Bake in oven 200 ° C for 5-10 minutes (depending on size).
Butter Fry the meatballs before serving in order to get a good surface and good taste.
(At Christmas time, I usually freeze the meatballs without frying them. That way I can fry them when defrosting without burning them)