Cook pasta according to package instructions. Drain. Set aside.

Meanwhile:

Add bacon to a large skillet over medium heat and cook, stirring occasionally, until crisp. Remove from heat. Using a slotted spoon, remove bacon and place on a paper towel lined plate. Remove all but 1 T bacon drippings from pan.

Return pan back to stove top on medium heat. Add butter and garlic and cook 1 minute. Stir in flour. Cook 1 minute. Slowly stir in milk, stock and black pepper. Continue to stir until smooth. Bring up to just a boil, then reduce heat to medium low. Cook until just starting to thicken.

Add drained pasta to skillet (if skillet is not large enough then return pasta back to its cooking pan and pour the sauce in with pasta) over medium low. Stir well. Add chicken and most of the bacon into the pasta mixture (reserving just a few pieces, if desired, to garnish serving plates). Cook just 2-3 minutes more to warm chicken, if needed.

Remove from heat and stir in cheese.

Serve in bowls/plates with reserved bacon on top.