Bring a large pot of salted water to a boil over medium-high heat.
Cook the penne to al dente, according to the time on the package directions.
Before draining the pasta, reserve 1 cup of starchy pasta water.
Heat a large high-sided skillet over medium heat.
Add the olive oil, shallot, and garlic. Cook for 2-3 minutes, or until the shallot is tender.
Next add the butter, lemon juice, and red pepper flakes. Stir until the butter has melted.
Add ½ cup of the starchy pasta water and stir for 1-2 minutes, or until the sauce begins to bubble and thicken.
Add the sun-dried tomatoes, kale, and penne. Toss to combine.
If the sauce is too thin, add another ¼ cup of the reserved pasta water.
Continue to cook the pasta for 1-2 minutes, or until the kale is just barely wilted and the sauce evenly coats the pasta. Again, if the sauce becomes too dry add the last ¼ cup of pasta water.
Remove the pan from the heat and add the parmesan.
Stir to combine and season with salt and pepper to taste.
Store any leftovers in an airtight container in the fridge for up to three days.