Preheat the oven to 400 degrees. Line a baking sheet with parchment paper.
In a large bowl, combine the tomatoes, balsamic, olive oil, garlic, hot honey, and 1 tablespoon of tarragon. Season with salt and pepper, then set aside.
Lay the puff pastry sheet on a clean, lightly floured surface. Using a rolling pin, gently roll out the sheet to stretch slightly. Move the pastry sheet onto the parchment paper-lined pan.
Sprinkle the shredded cheddar and havarti (or gouda) over the surface of the pastry sheet, leaving about a ½ inch of space around the border. Layer the tomatoes on top of the cheese, pressing in slightly to adhere. Arrange the tomatoes in any order or design you’d like.
Fold the edges of the pastry inward to enclose the tomatoes. Brush the edges with beaten egg and sprinkle with either garlic salt or everything bagel spice.
Transfer to the oven and bake for 18-23 minutes or until the pastry is golden brown and the tomatoes burst.
Top with the remaining tablespoon of tarragon, shaved Parmesan, a heavy drizzle of hot honey, and freshly cracked black pepper. Serve it up!