1 1/2 teaspoons unsalted butter $
2 leeks, white part only, trimmed and thinly sliced
4 cups unsalted chicken stock $
1 teaspoon chopped fresh thyme
5/8 teaspoon kosher salt $
1/4 teaspoon black pepper $
2 cups frozen green peas $
1 pound fresh asparagus, trimmed and coarsely chopped
1/4 cup chopped fresh flat-leaf parsley, divided
1 tablespoon white vinegar
4 large eggs $
2 teaspoons extra-virgin olive oil $
4 (1/2-ounce) pieces crusty multigrain bread, toasted