Using a mandolin slicer, slice carrots and zucchinis into lengthwise strips about 1/8 in.(3 mm) thick. Place strips in large colander; sprinkle on 3/4 tsp (4 mL) salt; toss to coat. Drain in colander 30 min. (salting releases excess moisture in the vegetables). Transfer strips to layer of paper towels, pat dry. Wipe out the bowl, return strips into it.
Preheat oven to 400ºF (200ºC). In small dish, mix olive oil, thyme, garlic, remaining salt and pepper. Drizzle over vegetable strips; toss to coat. In an 8-in. (20-cm) square baking dish, place a single layer of carrot strips in the bottom, followed by a layer of green zucchini, then a layer of yellow zucchini. Repeat layers until all veggie strips are used up.
Cover dish with foil; bake 30 min. Remove foil; return dish to oven 15 to 20 min. until vegetables are tender and liquid has evaporated. Sprinkle panko and Parmesan cheese overtop. Broil 1 to 2 min. until top is golden brown.
Let rest 15 min. before slicing and serving.
For an indulgent version, add heavy cream and grated Cheddar to olive oil mixture