Roughly chop the onion and add it to a food processor with the parsley and cilantro. Pulse together until it's finely chopped. Set aside.
Using a box grater or hand grater, grate the potatoes, carrots and zucchini. Add the grated vegetables to a thin dish rag or cheese cloth and squeeze out as much liquid as you can, then discard the liquid.
Add the grated vegetables to a mixing bowl with the onion herb mix, ground beef, eggs, breadcrumbs, spices and 2 tbsp of olive oil. Mix well to evenly incorporate everything.
Pan-fry instructions
Heat a large skillet on medium heat with 1/4 cup of neutral oil. Shape the mix into palm-sized patties and pan-fry for 5-6 minutes per side.
Baking instructions
Line a large sheet-pan with parchment paper. Shape the mixture into palm sized patties and add them to the sheet-pan. Drizzle with olive oil and bake for 20-25 minutes on 400 F, flipping halfway through. You can set them under the broiler at the end to brown.