I assume you're talking about what my grandmother called karnatzlach. There are quite a few recipes for it on the web (but search for karnatzlach, not karnatzel).
If you look on page 289 of this googlebooks Encyclopedia of Jewish Food by Gil Marks, who is a great authority on Jewish cooking:
there's a recipe that looks exactly like what my grandmother made. It's really very easy because it's basically a very garlicy hamburger shaped like a hotdog. In the Gil Marks recipe he calls for 6-12 cloves of garlic for 3 lbs of beef (not too lean). The beef is ground very fine and the garlic is smeared with salt or pureed in a blender. He mixes the garlic and meat with a cup of water and lets it stand overnight in the fridge for the garlic to really permeate. I don't remember my grandmother doing that. She just mixed the meat and garlic, shaped it and grilled or broiled it. He also adds a tablespoon of baking soda after it has stood overnight and before shaping it. He says it makes the patties springy and juicy. You can also add chopped parsley, ground black pepper, cumin or allspice.