Place chicken tenders in a large ziplock bag. Add the lemon juice, 1 Tbsp olive oil, salt, and black pepper. Seal the bag and swoosh around to mix. Let sit for 30-60 minutes before you intend to make and serve the pasta.
After marinating the chicken, prepare a large, heavy bottom pot or tall sided skillet with remaining 2 Tbsp olive oil and set to medium heat. Place the chicken tenders on the skillet and cook for 3 minutes on each side. The chicken should be *just* cooked through, reading 160 F on a thermometer. Remove chicken tenders and place on a cutting board to rest. Take the skillet or pot off the heat.
Prep: Finely dice the shallots. Once diced, slice the rested chicken into strips for later. In a new pot, begin boiling water for cooking your pasta.
Add more olive oil to the skillet as needed and set back onto medium heat. Add the diced shallots and stir for 3 minutes, or until translucent. Add the garlic and butter at once. Stir everything together for 3-4 minutes, until everything is fragrant and bubbling. Add the tomato paste and chilis. Stir and fry off the tomato paste for at least 5 minutes, ensuring it is a deeper maroon and cooked through. In the meantime, add your pasta and 1 Tbsp salt to the boiling water.
Add ¾ cup heavy cream and ½ cup of pasta water to a bowl or heat proof measuring glass. The pasta water will help warm the cream and better mix into the sauce. Add the warm cream and pasta water mixture into the tomato sauce base. Stir for a few minutes until the sauce is a rich orange tone.
When the pasta is cooked at al dente, add the drained pasta and sliced chicken into the sauce. Keep more pasta water aside in the glass in case you need more to loosen the sauce while combining everything together. I keep the sauce wetter than normal because the pasta absorbs it fast once off the heat. Taste for salt! Serve pasta with parm and fresh basil!