tasty and easy. doubled the recipe (to use one full can of tuna). swapped onion powder for green onion and 1-for-1 gluten-free flour instead of all-purpose. needed to add a bit more flour for the mixture to come together. made a thicker burger and needed to cover the pan so it could cook all the way though. had it on a bed of spinach / arugula and topped it with homemade red cabbage slaw. v good. next time I'll make the yogurt sauce and have it with the tomato / cucumber.