Preheat the oven to 350 degrees. Line a sheet pan with parchment paper (for easier clean-up) and set aside.
In a large mixing bowl add the lamb, beef, onion, herbs, breadcrumbs, parmesan, and eggs and using your hands mix it well until combined.
Roll the meatballs: Scoop about 3 Tablespoons or so (depending how large you want them) of meat and using your hands, roll into a ball. Place on a plate. Continue to roll meatballs until all the meat has been used up.
Heat a saute pan on medium-high heat, add about 2-3 Tablespoons of oil so it coats the bottom of the pan.
Optional Step - roll the meatballs in flour and shake off the excess before cooking. This will help to brown the meat.This step can be skipped and the meatballs will still sear nicely if you have the heat high enough.
When the pan is hot, add the meatballs to the pan and sear, about 3-4 minutes or so. Try to leave a little space between each if possible.
When the meatballs are a deep brown then flip them using tongs and sear on the other side, another 3-4 minutes or so.
Transfer the meatballs to a baking sheet (they’ll still be raw in the center) and finish cooking them in the oven for about 8-10 minutes. Check a meatball by cutting it in half, if it’s not cooked to your liking then continue to bake for a few more minutes.
Remove and enjoy right away or let them cool and use for meal prep!