Cook the lentils in salted water until tender, but not falling apart. Lightly steam, grill or blanch the veggies. If adding radishes, you can keep those raw and crunchy- (or feel free to grill them). If using chard, finely chop and wilt in a pan with a little olive oil, shallot or garlic, and salt and pepper.
Place the lentils, veggies, onion, garlic and mint in a bowl. Toss with the olive oil, lemon zest and juice form ½ a lemon. Season generously with salt, pepper and optional sumac. Adjust lemon, adding more if you like. If it’s bland, it most likely needs salt.
Make the optional Yogurt Sauce to lather on the bottle of the plate or platter.
Mix all the ingredients together in a small bowl
Smear the yogurt sauce on a platter (or individual bowls or plates) then top with lentil salad. Dive in.