Preheat the oven to 400 degrees.
Remove the stem from the cauliflower and cut the cauliflower head into four or five sections. Place one or two sections of the cauliflower, depending on size, into a food processor and pulse until cauliflower rice is formed, usually 3 or 4 pulses.
Repeat for each section of the cauliflower.
Place the cauliflower rice in a large bowl. Add the olive oil, garlic powder, salt, pepper and pumpkin seeds, and toss to combine.
Place the cauliflower rice mix on an oiled baking sheet and spread out evenly. Bake for 10 minutes, tossing once during baking. Remove and let cool.
While the cauliflower is baking, prepare the grape leaves. Rinse the grape leaves with water to remove the excess salt. Press the grape leaves with a paper towel to remove the excess water. Chop or shred grape leaves and set aside.
Chop or dice the cherry tomatoes, cilantro and green olives. Place in a bowl with the cauliflower rice, and then add the grape leaves. Toss together, mixing well. Add a squeeze of lemon juice, salt and pepper to taste, and red pepper flakes.
For a more authentic Mediterranean flavor, sprinkle with feta cheese crumbles and optional dried fig.