• Place the package of puff pastry in the fridge.
• Preheat the oven to 375F.
• Cover a baking sheet with some parchment paper.
• Peel the beets and cut them in half. Add a medium sweet potato to the sheet. Bake for 35 minutes until lightly tender but still firm.
• Prepare the remaining ingredients: vegan cheese, arugula or micro greens, pickled onions, dried spices.
• Open the box of puff pastry and remove one of the sheet. You should be able to open both flap easily and remove the pieces of paper. It it is too soft, refrigerate for 5 minutes.
• Using a rolling pin, lightly flatten the sheet preserving its square form.
• Cut along the two folds and cut three equal square from each panel. You should end up with 9 squares.

Assemble the tartlets

• Preheat the oven to 400 F.
• Place a small drizzle of balsamic glaze for each square.
• Top with some pickled onions, arugula or micro greens, some feta and or blue cheese.
  
• Add a few slices of beet and sweet potatoes. Season with salt, pepper, oregano and thymes.
• Place a square over each mount making sure that the edges cover everything and tuck it around it. You can use a fork and gently push down on the edges.
• Brush a little milk over each tartlets.
• Bake for 14 minutes until the top is golden. Let them cool down for a few minutes before serving and flipping them over.
  
• Serve warm as an appetizer or with a salad.