Trim the zucchinis, squash and eggplant by 2-inches on either end. Set the ends aside and cut the remaining veg into thin medallions using a mandoline. Cover slices and set aside.
Using a very sharp knife, cut four of the tomatoes into thin slices. Add the tomato slices to the rest of the vegetable slices.
Heat the olive oil over medium heat in a heavy bottom skillet until shimmering. Add the onion and sauté until translucent. About 3-5 minutes.
Add the garlic and sauté until fragrant.
Cut the remaining tomatoes into quarters and add them to the pan followed by the zucchini, squash and eggplant trimmings. Cook until slightly softened. About 5 minutes.
Add the wine and season with salt, herbs de provence and 1 tablespoon of thyme. Bring to a boil, then reduce to a simmer. Add the bay leaf, cover and cook for 20 minutes.
While the sauce is reducing, preheat the oven to 425 F.
Once the sauce looks nice and jammy, remove it from the heat and, using an immersion blender, puree until smooth. Set aside to cool slightly.
Sift flour, baking powder, baking soda and salt together in a large bowl. Pour the mixture into a large food processor fitted with a dough blade. Add the cheese and remaining thyme and blitz briefly to mix.
Set the food processor to low and add the butter cube by cube. Process until the mixture resembles a coarse meal.
With the food processor still running, add the mustard. Next, stream in the buttermilk and process until a dough forms.
Turn the dough onto a very well-floured surface - the dough will be quite sticky. Knead the dough briefly, then form into a square. Divide the dough into four even pieces.
Pour 3 tablespoons of the sauce in the bottom of four onion soup bowls. Arrange the vegetables slices in a spiral formation. Spoon the remaining sauce over top of the vegetables slices and top with a biscuit.
Place the bowls on a baking sheet and bake for 20 minutes or until golden brown.
Remove the pies from the oven and immediately brush the biscuits with honey and sprinkle with additional fresh thyme and sea salt.
Let cool for 10 minutes before serving.