In a large bowl, mix together all of the ingredients except the avocado oil until well combined.
Divide the mixture into 8 equal portions. Form each into patties about 3/4 inch thick and place on a waxed paper lined tray.
In a large skillet, heat 1 tbsp of the avocado oil over medium heat until shimmering. Add half of tuna patties and cook until golden brown on the bottom, about 3 to 4 minutes.
Carefully flip over and cook the other side another 3 to 4 minutes. Remove to a paper towel lined plate and repeat with the remaining oil and patties.
Top with mayo, lemon, and capers, if desired.
Notes
Air Fryer Instructions:Spray or brush the air fryer rack with oil. Brush melted butter over both sides of the tuna patties and place on the rack. Air fry at 350F for 10 minutes, carefully flipping halfway through cooking.Storage Information: Store the patties in a covered container in the fridge for up to 4 days. You can also freeze them for several months.