Preheat the oven to 400º F.
Heat 1 tablespoon olive oil in a small sauté pan and add the onions. Saute on medium-low until soft and seem to melt. Remove from the heat and set aside.
Slice the pears, with the skin on, into wedges about 1/4" thick. Remove the seeds. Place on a baking sheet. Slice the endive in half, lengthwise, and place on the baking sheet. Slice the figs in thirds, lengthwise, and place on the baking sheet. Combine the last tablespoon of olive oil with the Pear Vinegar, a pinch of salt and pepper and swish around. Drizzle the vinaigrette over the fruit and endive and gently, gently rub it over everything for good coverage.
Oil and heat up the grill and place a lightly oiled vegetable grilling sheet on the grill. Place the endive on the grill, cut side facing down, and the fruit on the vegetable grilling sheet.
Grill the endive until the edges begin to brown and it begins to soften just a bit, turning it as needed (about 4-5 minutes total over direct heat). Grill the fruit until the pears begin to brown and slightly caramelize and the figs soften and become slightly juicy. Remove everything from the grill back to the baking sheet you started with.
Combine the cheeses, fresh thyme, and a pinch of salt and pepper in a small bowl with a fork.
Assemble the flatbreads: spread the cheese mixture onto the Na'an. Sprinkle on the sautéed onions and layer the pears, endive and figs on top. Bake until the cheese melts a bit - about 15 minutes.
Remove from the oven and slice up into bite-sized pieces. This can be served at room temperature, but is oh so much better warm.
And as a final note, if you didn't hit on the above link for Grey Poupon, I recommend doing it. It might not be the one you grew up with like I did.