Mix the flour and salt. Make a hole in the center of the flour and mix in the eggs with a fork, gradually adding in more flour until it comes together as a dough. Knead the dough on a counter for 5-10 minutes, until the dough is smooth. Cover well and let rest for 1 hour.
Sweet Potato + Kale Filling
Boil and mash the sweet potato and measure out 1/2 cup. Let cool.
Heat a frying pan over medium heat and drizzle with oil. Add the red onion and kale. Cook, stirring for about 5 minutes or until softened and cook through.
Add the salt, pepper, and thyme and heat through, then let the mixture cool.
Mix together the mashed potato, the kale and onion mixture and then add the Parmesan and ricotta. Set aside while you roll the pasta sheets.
Roll the Dough
Prepare a lightly floured cookie sheet to set the formed ravioli onto.
Cut the dough in half and begin feeding it through the pasta roller. Roll at setting "1" about five or six times until you have a smooth sheet of pasta the same width as the pasta roller.
Feed the dough through settings "2" and "3" twice each.
Feed the dough through settings "4" to "8" one time each.
Cut the dough in half and cover the portion you're not using.
Set a sheet of pasta dough in front of you. You'll place the filling on the bottom half of the dough and then fold the top over. Place 2-3 teaspoons of filling along the bottom of the sheet, about an inch apart.
Wet the dough all around the filling and then fold over the top of the sheet. Press out all air bubbles and stick the dough together. Trim edges and cut each ravioli out by dividing dough into squares with a knife. (You can also use a cookie cutter)
Let the ravioli sit on a parchment lined sheet or floured sheet, under a towel while you repeat with the other half of the dough.
Boil a large pot of well-salted water and boil the ravioli for 2-3 minutes, or until they float.
Lemon + Thyme Cream Sauce
Melt butter in a large sauté pan over medium heat until sizzling. Add the flour and whisk together and then let cook for a minute or so until you can't see any raw flour.
Add the milk slowly while whisking. It'll turn into a ball and then into a paste until it finally thins out a bit. Add the cream, lemon, thyme, salt, and pepper and whisk until heated through. Set aside until the ravioli is ready. (You can leave it on low heat) Use additional milk to thin it out, as needed.
To Serve
Plate the ravioli and drizzle with the sauce. Or toss the ravioli in the sauce. Garnish with Parmesan cheese, fresh ground black pepper, and chopped fresh herbs like basil, thyme, or parsley.
Notes
Tips
Knead: Make sure to knead the dough until it's smooth and elastic. This can take 5-10 minutes. This is essential to developing the gluten.
Rest: Letting the dough rest for 30-60 minutes lets all of that developed gluten relax a little so that the dough is easier to roll out. If it keeps shrinking back on itself too much, let it rest a bit longer.
Roll: Using a pasta roller is the easier way to get thin pasta sheets. You want ravioli sheets to be thin because you double them up when filling and shaping them.
Customize: You can swap in your favorite fillings or sauce in this recipe, just use the instructions for making the pasta dough and then customize it.
Store leftover ravioli and sauce in the fridge for 3-4 days.Reheat the sauce in a saucepan over gentle heat.Reheat the ravioli in the microwave by splashing water on and adding a lid. Heat in 30 second increments, stirring, until heated through.