In a large mixing bowl, combine all ingredients except oil and butter. Stir to combine and then with your hands, form patties. Use an ice cream scoop for easy portioning. Flatten them into ½” patties. (Should make about 8-10 patties)
Refrigerate the patties for 30 minutes.
Heat the butter and oil in a large skillet over medium-medium low heat. Add some of the patties to the hot skillet (don’t crowd the pan - you want at least an inch between patties). If it seems like the patties are browning too quickly, reduce the heat. Cook 3-4 minutes per side, or until golden and crispy on both sides. Transfer to a paper towel lined plate to drain. Repeat until all patties are cooked through.
Serve with homemade tartar sauce and lemon wedges on the side.
Notes
If the mixture is too moist to hold the patty shape, add more bread crumbs and if it is too dry, add an extra tablespoon of mayo.
Patties can be formed and stored in the fridge up to 2 days in advance of cooking.
These are best when eaten fresh; store leftovers in an airtight container for up to 3 days and reheat in a 350 degree oven for 10 minutes.