Make the dough: Mound the 2 cups harina de trigo más para espolvorear on a clean work surface and make a well in the center. Crack in 2 whole 3 huevos 2 enteros and 1 yema de huevo, then add the 2 tbsp aceite de oliva and ½ tsp sal fina. Using a fork, beat the 3 huevos 2 enteros gently, gradually incorporating 2 cups harina de trigo más para espolvorear from the inner walls of the well. Once a shaggy dough forms, switch to your hands and knead for 8–10 minutes until smooth, elastic, and slightly tacky — it should spring back slowly when poked. If it's too stiff, add 1 tbsp agua fría a teaspoon at a time.

Wrap the dough tightly in plastic wrap and let it rest at room temperature for at least 30 minutes. This relaxes the gluten and makes it much easier to roll thin.

Make the filling: In a mixing bowl, combine the ricotta, ½ cup queso Parmesano, ½ cup mozzarella fresca picada finamente, 1 yema de huevo, ½ tsp sal fina, ¼ tsp pimienta negra, ¼ tsp nuez moscada, and 1 tbsp perejil fresco picado finamente (if using). Stir until smooth and well combined. Taste and adjust seasoning. Transfer to a piping bag or Ziploc bag with a corner snipped off. Refrigerate until ready to use.

Roll the dough: Divide the rested dough into 4 equal pieces. Keep unused pieces covered. Using a pasta machine, flatten one piece into a rough rectangle with your hands, then feed it through the widest setting (1). Fold it in thirds like a letter and feed through again. Repeat 2–3 times. Then roll progressively thinner, one setting at a time, down to setting 5 or 6 (about 1–2 mm thick). Alternatively, use a rolling pin to roll as thin as possible on a lightly 2 cups harina de trigo más para espolvorear dusted surface.

Cut hearts: Using a heart-shaped cookie cutter (about 3 inches wide), cut as many hearts as possible from the sheet. Re-roll scraps once to cut more. You'll need an even number of hearts — half for the bottoms, half for the tops. Lay them on a lightly 2 cups harina de trigo más para espolvorear dusted baking sheet and cover with a clean towel to prevent drying.

Fill the ravioli: Lightly brush the edges of half the heart-shaped pieces with 3 huevos 2 enteros wash. Pipe or spoon about 1 tsp of filling into the center of each brushed heart, keeping a clear 1/2-inch border around the edges. Don't overfill — this is the most common cause of ravioli bursting.

Seal the ravioli: Place a second heart on top of each filled heart, aligning the edges. Starting from the top center point of the heart, press firmly outward toward the edges, pushing out any air pockets as you go. Press the edges firmly to seal. For extra security, crimp the edges with a fork. Place finished ravioli on a 2 cups harina de trigo más para espolvorear dusted baking sheet in a single layer.

Cook the pasta: Bring a large pot of agua fría to a rolling boil and add the 1 tbsp sal kosher para el agua de cocción. Working in 2 batches, gently lower the ravioli into the 1 tbsp agua fría. Cook for 3–4 minutes, until the pasta edges are tender and the ravioli float to the surface. Remove with a slotted spoon and set aside. Reserve ½ cup of pasta 1 tbsp agua fría before draining.

Make the brown butter sage sauce: While the ravioli cook, melt the 6 tbsp mantequilla sin sal in a large skillet over medium heat. Add the smashed 1 diente ajo ligeramente aplastado clove (if using) and the 8 hojas de salvia fresca enteras. Cook, swirling the pan occasionally, for 3–4 minutes until the 6 tbsp mantequilla sin sal turns golden-brown and smells nutty, and the 8 hojas de salvia fresca enteras turn crispy. Remove the 1 diente ajo ligeramente aplastado. Season with ½ tsp sal fina. If the sauce looks too thick, add a splash of reserved pasta 1 tbsp agua fría to loosen it.

Finish and serve: Add the cooked ravioli to the skillet with the brown 6 tbsp mantequilla sin sal sauce. Gently toss or spoon the sauce over the ravioli to coat. Divide among warm plates, spoon any remaining sauce over the top, and finish with freshly grated queso Parmesano and a few hojas de salvia fresca enteras for garnish. Serve immediately.