01 - Bring a large pot of generously salted water to a rolling boil. Introduce the spaghetti or linguine and cook until perfectly al dente, following the package directions. Reserve approximately 1/2 cup (120 ml) of the starchy pasta water before draining.
02 - While the pasta is cooking, heat a large skillet over medium heat. Add the diced bacon or pancetta and cook until it reaches a golden, crispy texture. Incorporate the unsalted butter and minced garlic, sautéing for one minute until fragrant. Remove from heat.
03 - In a separate mixing bowl, vigorously whisk together the 2 large eggs, grated Parmesan, Pecorino Romano (if employing), heavy cream (if using), and a liberal amount of freshly ground black pepper until a smooth, cohesive mixture forms.
04 - Fill a shallow saucepan with water and bring it to a gentle simmer over low heat. Add the white vinegar. Carefully crack each of the 4 large eggs into individual small ramekins, then gently slide each egg into the simmering water. Poach for approximately 3 minutes, or until the whites are set but the yolks remain lusciously runny. Delicately remove the poached eggs with a slotted spoon and place them on absorbent paper towels.
05 - Add the drained pasta directly to the skillet containing the rendered bacon and sautéed garlic. Toss thoroughly to coat the pasta. Allow the mixture to cool for approximately 1 minute before quickly incorporating the egg and cheese mixture. Toss rapidly to emulsify and create a creamy sauce. If the sauce appears too thick, gradually add the reserved pasta water until the desired consistency is achieved.
06 - Divide the finished carbonara evenly among four serving bowls or plates. Create a slight indentation in the center of each portion and carefully place one perfectly poached egg atop each serving. Garnish generously with freshly chopped parsley, additional grated Parmesan cheese, and an extra grinding of black pepper.
07 - Serve the Breakfast Carbonara immediately for optimal enjoyment.