Slice off the stem ends of the jalapeños, then halve them lengthwise. For less heat, scrape out the seeds and membrane, then cut into chunks.
Peel the garlic cloves and crush them.
Add the jalapeños, garlic, lime juice, olive oil, salt, and pepper to a tall jar, then pulse with an immersion blender until broken down.
Add the remaining sauce ingredients, then blend until smooth.
Taste and add more salt or pepper, if desired. Set aside.
Cut the chicken breast into bite sized pieces and season with salt and pepper.
Heat a few swirls of olive oil and some butter or ghee in a large skillet over medium heat. Once it is hot, add the seasoned chicken pieces.
Cook the chicken through. This takes 10-15 minutes. Flip at the halfway point to brown both sides.
Meanwhile, cook the pasta according to the package instructions. Use liberally salted water to cook your noodles in. Reserve some of the pasta water when you drain it. Leave the noodles in the strainer.
Add the sauce to a large mixing bowl with 2-3 tablespoons of the reserved pasta water and stir.
Add the pasta to the bowl and toss with the sauce. Add the cooked chicken pieces and toss again.
Serve warm, topped with parmesan cheese and pepper flakes, if desired.