Toss Cheddar and Romano cheese in a medium bowl to blend. Stir in the crème fraîche, 3 tablespoons chives, 2 tablespoons parsley and lemon peel. Season to taste with salt and pepper.
Line a baking sheet with parchment or saran wrap. Lay out the wonton wrappers on the baking sheet, in a single layer. Place 1 heaping teaspoon of cheese mixture in the center of each wonton wrapper. With a silicon brush, brush the edges of each wrapper with egg white. Fold wrapper corner to corner, and then press the edges to seal.
Repeat with remaining wonton wrappers and filling. You can make the raviolis ahead of time. Cover the baking sheet with saran wrap and refrigerate for up to 6 hours. You can also freeze for up to 1 week.
In a small saucepan, over high heat, boil the broth and butter, about 5 minutes. Whisk in remaining chives and 1 tablespoon parsley. Season to taste with salt and pepper. Keep warm on low heat.
Bring a large pot of water to boil. Once boiling, add a generous pinch of salt and cook the ravioli. The ravioli will float to the top when done, which should only take about 3 minutes.
Using a slotted spoon, transfer ravioli to individual bowls, ladle broth mixture over the ravioli and serve immediately.
From Bon Appetit magazine, recipe from Bath’s restaurant in Paris