Sift the cocoa into the flour. Make a mound with the flour mixture, add a pinch of salt. Then make a well in the middle in which to put the eggs. Beat the eggs with a fork and then slowly use the fork to incorporate the flour. Use your hands to knead the dough for 10 minutes until smooth. (Of course, you can use a kitchen mixer with a knead attachment to accomplish the foregoing.) Wrap the dough tightly in plastic and set aside in a cool, dry place for 20-30 minutes.
Cut the dough into 4-6 pieces of equal size, but use only one piece at a time (leaving the remaining dough wrapped in plastic). If you are doing this the old fashion way, with a rolling pin, then roll it out, fold it back several times, and continue this process until thin. Alternatively, pass it through a pasta machine until thin (or until it goes through the second thinnest setting at least twice). Fold the pasta in half and then half again and then cut into desired width (about 1/3 inch for pappardelle) and place on a towel to dry or rack for a couple of hours until ready for use.
For the Ragu:
In a large pot, over medium heat, sauté the garlic until golden. Add the ribs and sear the sides. Add the tomatoes, salt, and pepper to taste. Reduce the heat to low and simmer for 3 or so hours, stirring regularly, until thickened and meat is tender or is incorporated into the sauce.
Bring a large pot of salted water to a boil.
Cook the pasta and drain. Place the pasta in a serving bowl and coat with sauce. Serve with a sprinkle of grated Parmigiano.
Remove any remaining ribs to a separate platter, and serve alongside or after the pasta.
Prep time will be 60 minutes if making fresh pasta. Also, sauce can simmer 3+ hours.