Force peas through the fine disk of a food mill into a bowl to remove skins.
Cook shallot in oil in a small skillet over moderately low heat, stirring occasionally, until softened.
Remove from heat and stir into pea purée with cheese and crumbs. Season filling with salt and pepper.
Put 1 won ton wrapper on a lightly floured surface, keeping remaining wrappers covered with plastic wrap, and mound a level teaspoon of filling in center. Lightly dampen edges of wrapper with a fingertip dipped in water and fold over to form a triangle, pressing down around filling to force air out and pressing edges together firmly to seal. Moisten 1 end of long side of triangle and fold opposite end over, creating a little hat shape, then pinch ends together to seal.
Transfer to a dry kitchen towel and make 17 more ravioli in same manner.
Combine broth, garlic, zest, and salt and pepper to taste in a saucepan and bring to a simmer. Cook ravioli in a large pot of boiling salted water until al dente, 2 to 3 minutes, then drain.
Divide ravioli among soup plates (3 each) and ladle broth over them, discarding garlic.
• Ravioli may be made, but not cooked, 1 day ahead and chilled, covered, in a pan lined with a dry kitchen towel.
