Wash the cauliflower and remove the outer leaves. If you find any little black spots, remove them with a paring knife. Cut the cauliflower in half (vertically) and then cut out the middle core. Discard the core.
If using a food processor, cut the florets into 1-inch pieces, and place them inside the food processor. Pulse(do not turn it on and let it go) a few times until it begins to break down. Continue pulsing until you have a rice-like consistency throughout.
If using a cheese grater,cut the cauliflower halves into 2 or 3 large pieces, and manually grate them using the cheese grater side.
To cook in a pan:
Heat a non-stick or large pan over medium heat. Once hot, add the oil or butter and move it around to coat the pan. Add the garlic and sauté for about 30 seconds until fragrant. Add the cauliflower rice and salt, and sauté until it's tender, for about 3 to 5 minutes. When it's nearly ready, add the lime juice and cilantro, and stir to combine.
To cook in the microwave:
Place the cauliflower rice and the minced garlic in a microwave-safe (glass or porcelain) baking dish. Cover with plastic wrap (or if yours has a lid, use that), and microwave for 3 minutes.
Remove from the microwave, carefully lift the lid or plastic wrap, and stir with a fork. Drizzle the olive oil or butter on top, pour the lime juice, cilantro, and salt, and mix to combine. Cover again and microwave for an additional minute. Test for tenderness.
Storage:
Refrigerate cooked leftovers in an airtight container for up to 4 days uncooked cauliflower rice for up to 1 week. Freeze uncooked cauliflower rice in a freezer bag, in portions, for up to 2 months.