Preheat your oven to 400°F and line a baking sheet with parchment paper.
Cook the bacon in a large skillet set over medium to medium-high heat until just crispy. Add the herbs, garlic, and black pepper. Cook for about 2 minutes until fragrant. Remove from heat.
To a food processor, add the flour and butter. Pulse until fine crumbs form (about 8-10 pulses). To a large bowl, add the flour and butter mixture. Pour in the buttermilk, parmesan cheese, 1 1/2 cups cheddar cheese, bacon mixture, and a dash of salt.
Lightly flour a clean surface. Pour the dough out onto the surface and knead into a soft dough ball. Roll out the dough with a rolling pin to about 1 1/2 inches thick. Using a 2-inch round cookie cutter. Cut the flour into rounds. Repeat using any leftover dough. Place the scones onto the baking sheet and brush with egg. Sprinkle with coarse sea salt if desired.
Bake the scones for 20-25 minutes or until golden brown.
Meanwhile, make the cultured butter. With a stand mixer or electric hand mixer, beat the créme fraîche until it turns to butter. Season with fine sea salt. Serve the butter with the scones.