With the rack in the middle position, preheat the oven to 350ºF (180ºC). In a large bowl, whisk together the egg, oil, mustard, salt, and red pepper flakes. Add the bread crumbs and mix just enough to moisten everything.
Press the mixture into six lightly oiled tartlet moulds about ten centimeters in diameter and with removable bases.
Place on a baking sheet. Bake for 20 minutes or until the crusts are golden. Let cool completely on a wire rack. Unmould and place on a serving platter.
Filling:
In a bowl, season the ricotta with salt and pepper and mix well. Divide the ricotta evenly between the tartlets.
In another bowl, gently toss the cherry tomatoes with the remaining ingredients. Season with salt and pepper. Top the tartlets with the tomato mixture.