Make sure your oven racks will fit your covered dutch oven, move as necessary to ensure the dutch oven will be in the middle of your oven. Preheat the oven to 250°F.

Remove the giblets and neck from the chicken. Pat the chicken dry and sprinkle with salt and pepper.  Stuff several pieces of onion and 3 of the cloves of smashed garlic into the cavity of the bird.

In a large dutch oven, heat the olive oil over medium high heat. (your dutch oven should be at least as large as your chicken-I use a 5 quart dutch oven for a 4 pound chicken, I go to my 7 quart dutch oven for any larger chicken).

Add the chicken breast side down and cook until browned (approximately 5 minutes).  Using a wooden spoon, flip chicken.  Add onion and remaining garlic to the bottom of the pan. Cook breast side up until bottom is browned (approximately 5-6 minutes).  

Place rosemary and thyme on top of chicken.  Cover dutch oven with aluminum foil and then cover.  Place into oven and cook until breast registers 160°F on a meat thermometer.  (about 80 minutes for a 4 pound chicken)

Remove chicken to a cutting board (or I use my cast iron skillet for presentation on the table).  Remove rosemary and thyme from pot.  Add lemon juice.  Pour juices with onion and garlic into a jar.  Carve chicken as desired.  Serve juices with onion and garlic with the chicken.

Make sure you save your chicken carcass (bag it and throw it in the freezer).  We'll be using it soon!