Step 1 Bring a large pot of water, salted with 1 tablespoon salt per quart of water, to a boil. If the ramps are clean, trim the roots and rinse well. If they're not clean, slip off the first layer of skin then trim the roots. Remove wilted leaves, if any. Rinse the ramps in several changes of water, swishing vigorously. If the ramps have bulbs, cut the leaves apart from stems where they begin to branch, leaving most of the red stem on bulbs. Young ramps will not have pronounced bulbs or red stems.
Step 2 Place the whole young ramps (or bulbs) in the boiling salted water. Simmer until the thickest part can be pierced easily with a sharp knife, 2 to 4 minutes, or as size dictates. Lift the ramps or bulbs from the hot water and plunge into ice water, then drain and reserve.
Step 3Blanch the leaves (if using) in water for 30 seconds. Plunge them into ice water, then drain and reserve. If using whole young ramps, squeeze the moisture from them and coarsely chop half of them. If using bulbs, leave whole.
Step 4Optionally, heat 1 teaspoon olive oil in a small saute pan and add the bread crumbs. Lightly toast over low heat and set aside. Cool slightly then stir in the orange zest. If not using bread crumbs, reserve the orange zest for a later step.
Step 5Blend the vinegar, mustard and one-fourth teaspoon salt. Gradually add the walnut oil and the remaining 2 tablespoons olive oil, whisking to emulsify.
Step 6Arrange about 6 whole leaves or whole ramps on each of 4 serving plates. Stir several spoonfuls of dressing into the chopped ramps and spoon on next. If using bulbs, arrange them on the leaves. Drizzle with dressing. Sprinkle bread crumb-orange mixture or orange zest alone over top and serve immediately.