Boil large pot salted water. Add pasta shells, cook 8 minutes al dente. Reserve 1 cup pasta water with measuring cup. Drain colander.
Heat olive oil in large skillet over medium using measuring spoon. Add diced onions, cook 5 minutes soft golden with wooden spoon. Add ground beef, break crumble, cook 8 minutes browned no pink.
Stir garlic, cumin, paprika, salt, pepper from measuring spoons into beef. Cook 2 minutes fragrant. Add reserved pasta water, simmer 12 minutes thick sauce.
Add drained pasta to skillet with tongs. Toss wooden spoon 2 minutes till noodles coated glossy.
Stir yogurt and minced garlic in bowl till smooth creamy.
Plate pasta mounds. Dollop yogurt generous with spoon. Sprinkle parsley. Hit table hot.
