SOAK THE ZUCCHINI IN SINK FULL OF WATER FOR 30 MINUTES, THEN SCRUB OFF ANY DIRT OR SAND. TRIM THE ENDS, THEN SLICE LENGTHWISE IN HALF. CUT CROSSWISE INTO 1/2-INCH HALF MOONS. TOSS IN A COLANDER WITH A FEW TBSPS OF COURSE SALT (I USE MALDON). ALLOW TO SIT FOR AROUND 30 MINUTES. THE SALT WILL DRAW OUT SOME OF THE MOISTURE FROM THE ZUCCHINI.
RINSE OFF THE SALT AND ROLL THE ZUCCHINI PIECES IN A CLEAN DISHCLOTH.
IF YOU'RE USING LEEKS AND GREEN GARLIC, TRIM OFF THE ROOT END AND THE DARK GREEN LEAVES. SLICE LENGTHWISE AND DUMP INTHE SINK. USE YOUR HANDS TO CLEAN OFF ANY DIRT. DRAIN. PAT DRY. CUT CROSSWISE INTO 1/2-INCH PIECES.
IF USING REGULAR GARLIC, TRIM AND PEEL THE CLOVES. SLICE LENGTHWISE INTO THIN PIECES.
PEEL THE OUTER LAYER OF THE FENNEL BULB OF ANY DISCOLORED PATCHES. SLICE THE FENNEL LENGTHWISE IN HALF. CUT OUT THE SMALL TOUGH TRIANGLE OF FLESH AT THE BASE. CUT CROSSWISE INTO 1/2-INCH HALF MOONS.
SLICE THE CHERRY TOMATOES LENGTHWISE IN HALF.
HEAT ABOUT 3 TBSPS OF OLIVE OIL IN AN AU GRATIN DISH OR SHALLOW CASSEROLE OVER MEDIUM HEAT. ADD THE ZUCCHINI SAUTÉ FOR THREE MINUTES TOSSING FREQUENTLY SO THE SLICES BROWN LIGHTLY.
ADD THE LEEKS, GARLIC AND FENNEL. TOSS WITH THE ZUCCHINI AND COOK FOR ANOTHER MINUTE OR TWO.
FOLD IN THE CHERRY TOMATOES.
LAY THE COD FILLETS ON TOP OF THE VEGETABLES. SALT AND PEPPER. DRIZZLE SOME OLIVE OIL ON THE FISH.
PRE-HEAT BROILER. PLACE THE RACK SIX INCHES BELOW THE FLAME. (NOTE: BROILERS VARY, SO ADJUST RACK HEIGHT ACCORDINGLY.)
POUR IN 1/2 CUP OF WATER AND PLACE UNDER THE BROILER.
BROIL FOR ABOUT 5 MINUTES OR UNTIL THE FISH IS COOKED THROUGH.
SCATTER WITH CHIVES OR PARSLEY AND SERVE.
SERVES 2 TO 4
