Since I had no cream, I used a little extra low-fat milk. I also used one more whole egg than she suggests because, well, one slipped free when I cracked it with more gusto than intended. While Bill Smith steamed his vegetables first, I kept mine raw. The result was a tender, creamy custard with vegetables that maintained a light crispness and sunny freshness.
1 yellow zucchini
1 green zucchini
1 large tomato
2 purple spring onions
4-5 sprigs thyme
1/2 cup pecorino romano, freshly grated
4 whole eggs
1 egg yolk
1/2 cup low-fat milk
1/4 tsp. kosher salt
several grinds of black pepper
1 ready pie crust
Preheat oven to 350 degrees.
Bring pie crust to room temperature and roll lightly to increase circle by about an inch. Transfer to tart pan with removable bottom that has been lightly sprayed with oil. Cover with parchment and pie weights - I use a mix of beans and rice - and bake about 20 minutes.
Remove to rack. After about 5 minutes, remove parchment with pie weights and cool crust.
Using a food processor fitted with a 1/4-inch slicing disk, place tomato in feed tube and slice with light pressure. Transfer slices to a paper towel lined plate; lightly press another sheet of paper towel to surface. Set aside.
Place tart pan atop sheet pan covered with foil. Slice yellow and green zucchini separately. Arrange yellow slices in a concentric overlapping ring atop crust; follow with tomato slices. Strip leaves from thyme sprigs and sprinkle over tomatoes, then top evenly with half the cheese. Next, arrange green zucchini in a ring and top with scattering of onion.
Bake about 25-30 minutes or until lightly set. Transfer to rack to cool, lifting base from tart ring after 15 minutes. Serve at room temperature.