Bring a large pot of salted water to a boil and cook pasta according to package instructions.
Dice the chicken into small (roughly 1 inch) cubes. Season with the salt and pepper.
Heat the olive oil in a large skillet over medium heat.
Once hot, add in the chicken and cook on each side for about 3 minutes or until golden and the internal temperature reaches 165.
Set aside on a plate.
To the same pan, melt the butter.
Add in the shallot and saute for 2-3 minutes. Add in the minced garlic and saute an additional 30 or so seconds.
Add in the diced sundried tomatoes and tomato paste. Saute for 2-3 minutes.
Whisk in the flour.
Add in all remaining ingredients aside from the spinach.
Whisk until the sauce starts to thicken, then add in the cooked pasta, chicken and spinach.
Stir everything to combine, then let the flavors marinate for a few minutes.
Garnish with fresh basil, more red pepper, parmesan and enjoy!