Grind cumin, green cardamom, caraway, star anise in a mortar and pestle. Add to mixing bowl with yogurt.
Peel and crush garlic into a paste in mortar and pestle.
Stir yogurt, freshly ground spices, garlic paste, zest and lemon juice in a bowl.
Butterfly beef roast in a circular cut about 1 inch thick, lay open and spoon yogurt marinade over, leaving a small amount for the outside.
Roll up and tie with butcher's twine, spoon remainder of marinade on outside.
Cover with foil, marinade for 4 hours in refrigerator.
Heat charcoal or covered gas grill to medium. 300°F is target temperature. Once temperature is stabilized, roast beef for 2 - 2 1/2 hours, turning once each hour.
Roast until desired doneness, then remove and let sit on platter for 5 - 10 minutes. Slice and serve.
Grass-fed beef will be tough and chewy if cooked to the usual USDA temperatures most of us are used to. The USDA recommends the beef be cooked to 145 - 170°F, while 120 - 140°F is best for pastured or grass-fed beef. Shannon Hayes at www.grassfedcooking.com has taught me the most about bringing the rich and delicious flavors from these meats!Adapted from Saveur Magazine #163
From the Terroir Seeds test kitchen. Smoked Yogurt Marinated Beef Roast https://underwoodgardens.com/smoked-yogurt-marinated-beef-roast/