Bring a large pot of generously salted water to a boil over medium-high heat and cook the pasta until al dente, about 3 minutes. Drain the pasta, reserving ¼ cup of the pasta water, and toss the pasta in a little bit of olive oil right in the colander to keep it from sticking. Add the 3 tablespoons of the olive oil to the empty pasta pot, reduce the heat to medium-low, then add the garlic, cumin, and red pepper flakes. Cook over medium heat, stirring, until the cumin is fragrant and the garlic is light golden, 2 minutes. Add the tomatoes, cream, salt, and black pepper, reduce the heat to medium-low, and warm through, 2 minutes. Add the labaneh, warm through for another minute, then add the pasta and toss it in the sauce, adding a little bit of the pasta water if needed to loosen the sauce. Season with salt and pepper, divide among 4 bowls, and garnish with za’atar.