Step 1

Combine ½ cup chickpeas, water and 1 teaspoon oil in a mini food processor. Pulse until coarsely chopped. Transfer to a medium bowl and add the remaining ½ cup chickpeas, coarsely mashing with a fork. Add beef, mint, oregano, pepper and ¼ teaspoon salt; mix gently to combine. Form into four burgers, 3½ inches wide.

Step 2

Heat the remaining 1 teaspoon oil in a large nonstick skillet over medium heat. Add the burgers and cook, flipping once halfway, until an instant-read thermometer inserted into the thickest part registers 160°F, 3 to 4 minutes per side. Transfer to a plate, sprinkle with the remaining ¼ teaspoon salt and let rest for 5 minutes.

Step 3

Meanwhile, combine feta and yogurt with lemon zest and lemon juice in a medium bowl. Beat with an electric mixer on medium-high until fluffy, about 1 minute. Serve the burgers on buns with the sauce, lettuce, onion and tomato.