Carefully wash the clams under running water in order to remove any sand inside. In a pan heat the garlic and hot pepper cut in half with a drizzle of olive oil, add the clams and cook over high heat. Add the white wine and continue cooking until the clams open (after pouring the wine let it evaporate for a couple of minutes, then cover the pan with a lid).
The clams are ready in approx. 10 minutes. Cut off the tough root ends and the tender tips of the asparagus, chop the stems, sauté in a pan with a drizzle of olive oil, salt and pepper. Blend the sautéed asparagus, leaving some tips aside for garnishing later. Shell three quarters of the clams, keeping a few shells.
Boil the spaghetti in plenty of salted water, drain "al dente" and finish cooking in the pan with the cream of asparagus and a ladle of cooking water to keep them tender. Add the clams and garnish the dish with some asparagus tips.