In a large pot over high heat, bring 6 cups of water and 1 tablespoon of kosher salt to a boil.
Meanwhile, thoroughly wash 1 bunch of rapini under cool, running, drinkable water. Cut and discard the bottom 3 inches of the stalk.
Using tongs, add the broccoli rabe to the boiling water and submerge below the waterline. Cook until bright green and crisp-tender, testing for doneness after 2 minutes. Remove with tongs or drain into a colander set in the sink. Run under cold water until they are cool to the touch to stop them from cooking and set their vivid color.
Take a handful of blanched stalks and firmly squeeze them over the sink to remove as much water from the stalks and leaves as you can. Repeat with the rest of the rabe. Cut the stalks into 2-inch pieces and set aside.
In a large sauté pan over medium heat, combine ¼ cup of extra-virgin olive oil, 3 cloves of minced garlic, and ¼ teaspoon of crushed red pepper flakes.
When the garlic becomes fragrant, after about 2 minutes, add the chopped broccoli rabe and 2 tablespoons of chicken broth. Cook until the rabe is warmed through.
Remove from heat and season with kosher salt and a generous grating of Parmigiano-Reggiano. Serve warm or at room temperature. Eat up, Mama!