2 tablespoons olive oil
1 large or 2 medium onions, thinly sliced then chopped
1 clove garlic, pasted
Salt and finely ground black or white pepper
1 small fresh bay leaf
1/4 cup chicken or beef stock
3 tablespoons crème fraîche or sour cream
2 teaspoons Dijon mustard
12 hard-boiled eggs, cut in half and yolks separated
Crispy shallots or store-bought fried onions
Heat a medium skillet over medium heat with oil, 2 turns of the pan. Add onions, garlic, salt, pepper and bay, and cook, stirring frequently, to caramel in color, 30-35 minutes. Add stock and let absorb into onions. Let cool and remove bay leaf.
Combine the onions with the crème fraiche or sour cream, mustard and egg yolks; adjust seasoning to taste. Fill a food storage bag with egg mixture and trim a corner with scissors to form a disposable pastry bag.
Fill eggs and top with crispy shallots or fried onions.