If using flax egg, combine ground flax seeds with warm water and set aside.
Combine and thoroughly mix all the yogurt sauce ingredients together and let sit in the fridge until the patties are ready to be served
Sprinkle ¼ tsp of salt on the shredded zucchini, put in a colander and let sit to draw out any liquid.
Heat oil in a medium skillet and add garlic and green onions, ¼ tsp salt and pepper and cook until veggies are slightly soft. Remove from heat, drain off excess oil and allow to cool.
In a large bowl, combine breadcrumbs, panko, parmesan cheese and lemon zest. The mix in lemon juice, quinoa, rice, and cooked green onions and garlic. Add in egg and shredded zucchini. Mix everything together thoroughly and start forming balls (a little smaller than a golf ball) and then carefully flatten into a thick patty.
Preheat oven to 400 F
Heat oil (just enough to evenly cover the surface entirely) on medium-high heat in a large skillet. Carefully place patties into the pan and cook for a few minutes on each side until it starts to lightly brown and get a little crispy. Remove from pan and place to a paper towel covered plate. Dab off any excess oil with more paper towel.
Move patties onto a baking sheet and cook in the oven for 15 minutes, turning over at about the halfway point.
Remove from oven, allow to cool slightly and serve with the chilled yogurt sauce on top.