Heat the olive oil in a heavy-bottomed pot or tagine over medium-high heat.
Season the cubed lamb leg with sea salt and black pepper, then sear in the pot until browned on all sides.
Add the diced yellow onion, minced garlic, and grated ginger to the pot, sautéing for 3-4 minutes until the onion is translucent.
Stir in the tomato paste, ground cumin, coriander, and cinnamon, stirring constantly for 1 minute to toast the spices.
Pour in the beef bone broth and add the halved dried apricots, scraping the bottom of the pan to release any browned bits.
Bring the liquid to a boil, then reduce the heat to low, cover, and simmer for 45-60 minutes until the lamb is very tender.
While the lamb simmers, lightly steam or sauté the cauliflower rice in a separate pan until tender-crisp.
Serve the lamb tagine over the cauliflower rice and garnish with freshly chopped cilantro.