Preheat the oven to 400 degrees. Line one rimmed-baking sheet (jelly roll pan) with foil and top it with a wire cooling rack. Spray another rimmed-baking sheet with gluten-free, non-stick cooking spray then line it with a piece of parchment paper big enough to go up all the sides (it is easier to line the baking sheet if you crumble the parchment paper first).
In an electric mixer bowl, preferably fitted with a paddle attachment, combine the cream cheese with the ricotta until fully blended and smooth. Add the eggs and parmesan cheese and mix to combine. Pour the batter onto the baking sheet with the parchment paper.
Put the bacon in a large freezer storage bag along with the brown sugar and shake to coat the bacon. Lay the bacon on the wire rack. Put both baking sheets in the oven and cook for 20 – 25 minutes or until the pizza crust is very lightly browned and the bacon is crispy. Remove both from the oven and turn the oven up to 500 degrees.
Let the bacon cool. Once cool, chop it into pieces and set aside until assembling the pizza.
Let the crust cool in the pan for 5 minutes then remove it from the baking sheet along with the parchment paper. Place the parchment paper and crust on a flat baking sheet and put it in the oven for 5 minutes. Remove from oven and let cool. You want the pizza to cool completely so it dries up and is crispier. You can place it in the freezer for 30 minutes or let it cool on the counter and then refrigerate for several hours uncovered. Keep the crust on the parchment paper as it needs to go back in the oven once more and it is easier to move it about on the parchment paper.
Prepare the onions by combining the olive oil and butter in a large skillet over medium-high heat. Add the onions and turn the heat down to low. Let the onions slowly caramelize, stirring occasionally, about 40 minutes or until they are very soft and deeply brown.
When ready to assemble the pizza, preheat the oven to 400 degrees. Spread the mascarpone cheese in a very thin layer over the crust. Top with the caramelized onions, bacon pieces and pear slices. Bake for 10 minutes or until heated through. Sprinkle with fresh thyme leaves and black pepper. Cut into squares and serve.