Combine first set of ingredients in the bowl of a food processor and pulse until finely chopped - about 6 pulses. Do not overprocess.
Shape the mixture into 4 burgers. Set these on a plate so they are not touching, cover well with plastic wrap, and refrigerate for 1 hour.
Measure the flour and remaining 1 tbsp. salt into a large shallow bowl or pie plate and whisk together. Dredge the tuna burgers in the flour mixture so they are lightly dusted on both sides.
Place a skillet, preferably cast iron, over medium-high heat, add the oil, and let it get hot - about 2 minutes.
Arrange the burgers in the pan so they aren't touching. Cook uncovered for 2 minutes. Turn and cook about 2 minutes more. The burgers should be rare to medium-rare.
Serve on a hamburger bun.
we added home made onion rings and salad kids love it