- ½ cup plus 2 tsp. California Olive Ranch extra virgin olive oil, and more for the pan
- 1 Tbsp. finely chopped fresh mint
- 1 Tbsp. fresh orange juice
- 1 tsp. balsamic vinegar
- Kosher salt
- 12 oz. zucchini (about 2 small)
- 1 ½ lbs. small ripe tomatoes (about 5)
- 2 medium onions (about 10 oz. total), thinly sliced
- ½ cup fresh coarse breadcrumbs
- ¾ cup finely grated Parmigiano-Reggiano cheese
- 1 Tbsp. chopped fresh parsley
Preheat the oven to 375 degrees F. Grease a shallow 2-qt gratin dish with a little California Olive Ranch extra virgin olive oil.
In a medium mixing bowl, whisk the mint, orange juice, balsamic vinegar, 1 Tbsp. of California Olive Ranch extra virgin olive oil, and ¼ tsp of salt. Slice the zucchini thinly (between 1/8 and ¼ inch/3.25 and 6.5 mm thick) and slightly on the diagonal. Add them to the bowl and toss well. Core and slice the tomatoes crosswise a little thicker than the zucchini, and arrange them on a large dinner plate or platter. Sprinkle with ¼ tsp. of salt. Let both the zucchini and the tomatoes sit while you’re cooking the onions, or for at least 15 minutes. Toss the zucchini in the marinade occasionally.
Meanwhile, heat 2 Tbsp. of California Olive Ranch extra virgin olive oil in a medium (9- to 10-inch/23- to 25-cm) skillet over medium heat. Add the onions and ¼ tsp. of salt and cook, stirring frequently, until the onions are translucent and starting to turn golden brown (they should still have some body), 10 to 12 minutes. Transfer the onions to the gratin dish and spread them out in one layer. Let cool.
In a small bowl, combine the breadcrumbs, 2 tsp. of California Olive Ranch extra virgin olive oil, 2 Tbsp. of the Parmigiano, the parsley, and a pinch of salt.
Drain the accumulated juices off the tomatoes and zucchini. Starting at one end of the gratin dish, arrange the vegetables in rows with the slices slightly overlapping each other. (Arrange the first row so the pieces are resting against the back edge of the pan.) I like to alternate between one tomato slice and two zucchini slices (or one if they’re very large). Sprinkle a little bit of the Parmigiano over the zucchini slices as you go. If you need to fit in a few more rows, you can compact the rows slightly. Press gently to make sure the vegetables are level. Sprinkle any leftover Parmigiano over the vegetables and drizzle the remaining 2 Tbsp. of California Olive Ranch extra virgin olive oil over them. Sprinkle the breadcrumbs on top, letting the vegetables peek out a bit.
Bake until well browned all over and the juices have bubbled for a while and reduced considerably, 60 to 70 minutes. (The edges of the gratin will be very dark.) Let cool for at least 15 minutes before serving.
Chef's Note: I first learned to make a tian (a Provençal summer vegetable gratin) in culinary school years ago. Since then I’ve made so many crowd-pleasing versions of them that they have become a signature Susie dish. For this book, I developed a new version which I particularly like, because I’ve marinated the zucchini in a bit of orange juice and balsamic, and added fresh mint. These flavors give this gratin a nice, bright flavor.
I have to tell you my real secret to tian-deliciousness, though: I cook the gratin for a long time—long enough for the juices from the vegetables to greatly reduce and caramelize. (You’ll see a dark rim around the inside of the pan where some of the juices have caramelized while bubbling.) With those reduced tomato juices mingling with the sweet browned onions, the flavor is just intense. So don’t be tempted to undercook a tian, as even some experienced cooks do. When I say long time, I only mean an hour or so in most cases, but it’s that extra 20 minutes that usually makes the difference.
Recipe courtesy of Susie Middleton, Fast, Fresh & Green (Chronicle Books, 2010)