Cook pasta in salted water according to package directions. Drain, reserving 1 1/2 cups cooking water.

While pasta cooks, cook bacon in a large skillet over medium-high until crisp. Transfer bacon to a plate lined with paper towels to drain; reserve 2 tablespoons drippings in skillet. Chop or crumble bacon.

Add tomatoes to skillet, and cook, stirring often, until just softened, 3-4 minutes. Add shallots and garlic. Continue to cook, stirring often, for an additional 3 to 4 minutes.

Add 1 cup of the reserved cooking water and bring to boil. Remove from heat and stir in cooked pasta. Quickly stir in beaten egg yolks until everything is thoroughly combined. Return skillet to medium-low heat and cook, stirring constantly, until sauce is slightly thickened and creamy, 2 to 3 minutes.

Remove from heat and stir in bacon, and Parmesan cheese and cook until melted and smooth. Season with salt and pepper, to taste.

Stir in chives and parsley, adding remaining 1/2 cup cooking water if necessary to reach desired consistency. Garnish with additional Parmesan cheese before serving, if desired.