They may have a sophisticated French name—and a fancy look that puts regular deviled eggs to shame. But “Duxelles” really just means mushrooms and shallots sautéed in butter (yum!). The cooked mushrooms are folded into a creamy egg yolk mixture made with mayonnaise and Dijon mustard. Then, the mixture is spooned back into hard-boiled eggs. For a restaurant-quality effect, transfer the filling into a zip top plastic bag with a snipped corner (about ½ wide), and pipe it into your eggs. If you’re worried about the hors d'oeuvres sliding around while you carry the serving platter, try securing each egg into place with a tiny dot of filling.