3 lamb indian yogurt mint sauce Recipes

boneless lamb shoulder, trimmed and cut into 1-inch pieces, olive oil, divided, chopped onion, chopped shallots, minced garlic, divided, ground cumin, ground coriander, ground cardamom, ground mustard, ground turmeric, ground red pepper, grated whole nutmeg, chopped fresh mint, divided, kosher salt, divided, red bell peppers, low-fat greek-style plain yogurt, fresh lemon juice, freshly ground black pepper, divided, hamburger buns, toasted, torn radicchio

thick plain yogurt, mint leaf, finely chopped, dried red lentils, lean ground lamb, brown onion, grated, mild curry paste, diced tomatoes, chicken stock, water, steamed rice, to serve