Bring salted water to a boil and cook the pasta until your desired tenderness. Remember that the pasta will soften a bit as it absorbs the cheese. During the last few minutes of cooking the pasta, add the fresh broccoli florets into the boiling pasta water and cook until tender, about 3 minutes. Drain immediately and well and return to the pot.
Meanwhile, in a skillet or saucepan over medium high heat, cook slice bacon pieces until crispy.
Remove the bacon from the pan and to a paper towel to drain, reserving the bacon fat to start the roux.
Next, stir in flour, cooking until hot and bubbly, about 1 minute. Gradually stir in the milk. Add the salt and pepper. Continue to cook, stirring, until thickened and bubbly. Stir in the cheddar cheese and continue to cook and stir until cheese is melted. Add the cheese mixture into the pot with the pasta and broccoli, add the bacon and stir to combine.