Flatts.

Dear A.S.: Pesto Sauce is made with fresh basil leaves, and even with fresh spinach leaves. (Incidentally, do not use frozen or canned spinach if you want to try Spinach Pesto Sauce).

The word pesto comes from the grinding of the fresh leaves in a mortar with a pestle. The mortar and pestle is a dish and blunt instrument made from lava stone. Today's cooks use a convenient food processor with the same fine results.

Pesto Sauce is so easy to use you may find yourself making it often, but be careful: the ingredients are quite fattening! The following recipe calls for two tightly packed cups of basil leaves. Be sure you pack the cups tightly.

Fresh, washed spinach can be used as well, and here again, be sure you pack the cups tightly. Northern Italians use walnuts, while central and southern Italians like to use pine nuts. Walnuts contain less saturated fat and give the Pesto a sweeter, nuttier flavour. Use this sauce sparingly as the flavour is quite intense, but good.

PESTO SAUCE 2 cups fresh basil leaves, tightly packed 1 cup Parmesan cheese 1 cup virgin olive oil 1 cup walnut pieces 2 large garlic cloves 1 tsp. salt 1 tsp. pepper Put all ingredients into a food processor and process until smooth. Do not heat Pesto Sauce; Instead, toss it with hot pasta. Pasta with pesto sauce can be eaten hot, at room temperature, or chilled.

Dear Miss d'Arcy: Is bruschetta another name for garlic bread? T.O., Smith's.

Dear T.O.: No. Although bruschetta does have olive oil and garlic, it also includes tomato sauce and basil. I like to toast my cut French bread slices in the oven first. When still warm, I add my favourite tomato sauce, sprinkle it with olive oil, garlic and basil. I then return it to the oven and heat it.

After removing the toasted bread from the oven, I sprinkle it lightly with Parmesan cheese.

Dear Miss d'Arcy: Can you put fresh zucchini and yellow squash in a sandwich, and would it taste good? What kind of dressing could I use? N.K.D., Warwick.

Dear N.K.D.: You certainly can eat zucchini and yellow squash raw, and it will taste delicious! What I like to do, however, is lightly saute zucchini and yellow squash rounds with a little onion, shredded carrot and parsley in a little light oil. Then I put the veggies on a large whole wheat bun, top it with cheese, and stick it under the broiler until the cheese begins to melt (about 2 minutes.) I then spread some honey mustard over it before topping it off with lettuce and garden-fresh tomato slices.