Harvard beat. Bake that beet! Braise that lettuce! Roast that garlic!

ISN'T it a comfort to know how to deal with vegetables? Beets are simple enough, aren't they? They're always sliced and boiled. Maybe with a little sugar and vinegar. And certainly everyone knows endive is just a highbrow, imported, expensive salad stuffer, used mainly to impress your guests. Garlic is only for imparting a slightly ethnic flavor to maybe salad dressing or marinade.

Careful! OK, maybe rub a little on a leg of lamb before you roast it.

How incredibly easy to cook with vegetables this way! And how incredibly boring!

Just maybe it's time to serve them in a not so ho-hum way, and find out how wonderfully different they can be, in both flavor and texture.

Ever try braising a head of lettuce?

What about preparing a whole head of garlic to eat at a sitting? Would you gargle with Drain-O?

A number of restaurants have adopted more novel ways of cooking vegetables with success, even though their dishes haven't yet caught on.

``Beets? Oh, of course I love Harvard beets,'' a friend gushed as she drew her chair up to my dining room table.

Her comfortable smile became rather quizzical as she stared into a dish I had just uncovered.

``Baked beets?'' she said, sort of curling her top lip.

``Are you sure you can do that?''

Not only am I sure, but it has become my favorite way to serve them. Braised lettuce and endive are a wonderful change as well.

Cooking those leafy vegetables, usually relegated to a salad bowl, seems to astound people most. Try this: Braised Lettuce or Endive 2 small to medium heads lettuce (I like romaine, but others will do.) Butter 1 cup chicken broth Salt and pepper to taste 1/4 cup butter

Preheat oven to 325 degrees F.

Cut lettuce down middle lengthwise and rinse under cold water. Butter a shallow baking dish long enough to hold lettuce snugly. Place lettuce cut-side down in dish.

Boil chicken broth and pour over lettuce. Sprinkle with salt and pepper. Cover with foil and bake for 30 to 40 minutes.

Remove lettuce and fold in half to make a compact packet, and hold it in warm oven. Pour leftover juices in small pan and reduce to about two tablespoons. Whisk in 1/4 cup butter and pour over lettuce before serving.

Serves four.

You may braise a dozen heads Belgian endive this way, substituting 1 cup water mixed with 1 tablespoon lemon juice in place of chicken broth. Make sure you buy endive that has not yellowed.

The following dish is one of my favorites. Delicious as it is, it is wisely served on, say, a Friday night, when you have no other weekend plans!

Roasted Garlic in Chicken Stock 1 large head of garlic per person Chicken broth Salt and pepper to taste

Preheat oven to 350 degrees F.

Place 1 large head of garlic per person in small, shallow, ovenproof dish. Garlic should fit snugly in dish. Add chicken broth to about half cover garlic.

Bake for about 1 hour, or until garlic is soft when pierced with a fork. Check to be sure chicken broth does not evaporate completely.

Serve immediately.

Garlic will easily slip from skin when cloves are pressed gently with a fork. The garlic will be soft and buttery, and is especially good spread on crisp, buttered slices of French or Italian bread.

If you want to try just baked beets, prepare them the following way and serve them hot, without bothering with the other ingredients.

This full recipe, however, from Marcella Hazan, is quite a delicious, interesting salad.

Baking beets gives them a sweeter, nuttier flavor. They are quite a different vegetable cooked this way.

They may be baked by simply wrapping them in aluminum foil after they have been washed and trimmed.

Bake in a preheated 350 degree oven for 11/4 to 2 hours depending on size. Test for tenderness by pricking with toothpick. Cool before peeling. Baked Beets and Onion Salad 4 large beets (about 2 pounds) 1 large Bermuda onion 1 1/2 tablespoons red wine vinegar 1/2 teaspoon balsamic vinegar (this is an optional ingredient) 1/2 teaspoon salt 1/3 cup olive oil

Preheat oven to 350 degrees F.

Wash and trim beets and wrap each tightly in aluminum foil.

Cut a deep X in root end of onion, but do not peel them at this time.

Place beets and onion on oven-proof pan and and bake 11/4 hours.

Remove foil from beets and let stand 20 minutes. Peel them and cut into 1/3-inch-wide julienne strips.

Peel onion and cup into 1/2-inch strips.

Combine beets and onion in bowl.

Mix vinegars, salt, and oil in small bowl.

Add to beets and onion and toss everything thoroughly.

Let stand for several hours - tossing occasionally - before serving.

Serve at room temperature.

Serves 4 to 6 persons for a delicious meal of unHarvard beets.