Heat a grill to high (450° to 550°). Combine honey, garlic, 1/2 tsp. salt, and 4 tbsp. oil in a medium bowl. Add lamb and mix to coat well. Thread lamb onto skewers.
Meanwhile, put mint, parsley, kefir, pistachios, 1/4 tsp. salt, and remaining 6 tbsp. oil in a food processor. Pulse until pistachios are finely chopped, about 1 minute.
Put cannellini in another medium bowl. Mix in 1/2 cup pistachio mixture and remaining 1/2 tsp. salt.
Grill lamb until done the way you like, about 10 minutes for medium, turning once. Remove from heat. Spread beans on a platter and arrange lamb skewers on top. Spoon remaining pistachio sauce over lamb.
*Kefir is a tart beverage made with fermented milk. Look for it near the yogurt.