After the Roll is Over, THE BASKETS GATHERED BACK, the wonderful Easter dyes oohed, awed, and rubbed off on little hands, there is still hope for egg life after the bunny trail dies - or dyes. If you've been a smart egg dye director in the first place, you can stop reading here, because no doubt you blew the eggs out of their shells before you turned them over to the small decorators and you've already made terrific souffles, omelets and a grand scrambled egg pasta dish.But if you were hard-boiled about the whole operation - and if your Easter eggs didn't roll very far or weren't scrunched under bunny paws - now is the time to gather back your own basketful. The shells, crayon marks and all, can go right into the garden soil as excellent fertilizer. Les oeufs, hard-cooked, can go right into any number of fine French recipes. Or simply turn into deviled eggs. If you've had your eggs d'art out on the dining room table aound the chocolate Easter bunny centerpiece for a week, though, the best thing they can go into is the garden compost. The best way to tell if Easter eggs are sitll fresh is a quick taste. Now, on to the disguising, reviving and gourmetizing of not-just-another-pretty egg. Eggs with Mornay Sauce

Cut 6 hard-boiled eggs lengthwise into halves. Remove the yolks carefully and mash them with 4 tablespoons of butter until smooth.

In a skillet, melt one tablespoon of butter, add one tablespoon of olive oil and saute two tablespoons of minced onion until transparent. Stir in a quarter pound of finely chopped mushrooms and cook for two or three minutes. Add 2 tablespoons tomato puree, a handful of chopped, fresh parsley, 1/2 teaspoon salt and pepper to taste.

Take off the heat and mix in the mashed egg yolks very thoroughly. Spoon the mixture into the egg whites and place them ina greased baking dish.

Make a mornay sauce. Melt 4 tablespoons butter over low heat. Blend in 4 tablespoons flour and cook slowly, stirring constantly, until it froths - about 3 minutes. Take off the heat and beat in 2 cups milk until it is completely incorporated, then return to the burner and keep stirring until the mixture boils. Boil for one minute, then remove and beat in 3 egg yolks, one at a time. Fold in 1/2 cup grated Swiss cheese. Pour the mornay sauce over the stuffed eggs and place them in a preheated 425 degree oven.

Bake for six minutes or long enough to heat the eggs. Serve four. Poppy Seed Eggs

Chop six hard-boiled eggs together with a half-pound chopped, sauteed miushrooms. Mix in crumbled cooked bacon, about six slices. Cut six small hard rolls in half and hollow them out. Fill each half with the mixture. Mix one cup mayonnaise with three tablespoons Dijon mustard and three teaspoons poppy seeds. Spoon the sauce over each half roll and pop under the broiler until bubbly. Eggs Veloute

Melt 2 tablespoons butter over low heat; blend in 2 tablespoons flour and cook slowly, stirring constantly, until it froths (about 3 minutes). Remove from heat and stir in 1 cup chicken broth. (You can use canned consomme.) Whip briskly until well incorporated, then return to heat and keep stirring until the mixture boils. Boil for one mixture boils. Boil for one minute, remove from heat and add 4 tablespoons tomato paste.Coat warmed hard-boiled eggs with the mixture. (To warm hard-boiled eggs drop them in boiling water for 1 minute.) Sprinkle the coated eggs with grated Muenster cheese and slide under the broiler until slightly glazed. You can substitute any mild cheese for the Muenster. These make good appetizers. Brittany Eggs

Combine about one pound chopped sauteed mushrooms and about one cup chopped leeks cooked in butter.Cover the bottom of a baking dish with aprt of this mixture. place halved hard-cooked eggs on top and cover with remaining sauce. Place in a 400 degree oven long enough to heat through. Easter Eggs Out of the Shell

Combine 4 parts mayonnaise with one part Dijon mustard and juice from one lemon. Whip until smooth and light. Fold in one teaspoon finely chopped fresh dill. Halve eggs lenthwise, scoop out the yolks. Mix the yolks with three-fourths of the mayonnaise mixture and beat until completely incorporated. Stuff each egg white with the mixture and use the remaining mayonnaise to decorate the top of each half. Press capers and red caviar into the borders of the yolks in an Easter egg pattern. Chill for at least two hours before serving with wedges of pumpernickel bread.