Preheat oven to 350 degrees F (175 degrees C) and grease a 9-inch tart pan with butter.
Place the unbaked flaky pie crust (1) into the prepared tart pan.
Remove leaves from 3 sprigs of oregano and 3 sprigs of thyme.
In a bowl, whisk together 1 1/2 tablespoons of grainy Dijon mustard, 1 1/2 teaspoons of honey, 1 teaspoon of pressed garlic, and 6 tablespoons of olive oil to create a creamy paste.
Spread the mustard mixture evenly over the bottom of the pie crust.
Arrange 3 cut tomatoes over the mustard mixture, covering the bottom of the crust.
Sprinkle 1 tablespoon of grated Parmesan cheese over the tomatoes.
Top the tart with leaves from 1 sprig of oregano and 1 sprig of thyme.
Bake in the preheated oven for about 45 minutes, or until the crust is golden brown and the filling is cooked through.
Serve the tart warm or cold.