Heat the olive oil in a large skillet.
Add the chicken breasts to the skillet and season them with salt and pepper. Cook for about 5 minutes until the chicken is cooked through and starts to lightly brown.
Add the onions, garlic and cook for another 2 minutes until the onions softens a little bit.
Add the pasta, chicken broth, milk and bring to a boil.
Turn the heat down to low, stir, cover the pot/skillet and simmer for 12 minutes, stirring occasionally, until the pasta cooks through.
Uncover the pot and stir in the broccoli. Cover again. Continue cooking 5 more minutes.
Uncover and cook stirring until all the liquid evaporates.
Stir in cheddar cheese. Taste for seasoning and adjust with salt and pepper if needed.
