Preheat oven to 400 degrees Fahrenheit. Lightly grease a sheet pan.

In a small mixing bowl, combine goat cheese, kosher salt, black pepper, and basil with a spoon until evenly combined.

Place half of the pastry squares (18 squares) one inch apart on the sheet pan.

Allow the other 18 squares to defrost for five minutes on a cutting board. It’s important not to defrost completely. The dough should be stiff but not rock hard.

Carefully cut out a one-and-a-half-inch square from the center of each one, creating a little window frame.

With your finger, spread a little egg over one of the frames, then attach it to an uncut square using the egg as the glue. Do this for all of the pastries.

Now spread one teaspoon of cheese filling into the center of each of the pastries. Top with the grape tomatoes, two cut halves per pastry square.  

Using your finger again, spread egg on the frames. Sprinkle sesame seeds on the egg-coated outer frame.

Bake the pastries for 18 to 20 minutes at 400 degrees Fahrenheit.

If desired, drizzle the pastries with balsamic glaze before serving.