Preheat oven to 450 degrees F.
In a large bowl, place quartered gold potatoes and sliced carrots. Drizzle 1 tbsp olive oil, pinch kosher salt, and pinch black pepper, toss to combine. Dump vegetables into a large cast iron skillet or roasting pan. Nestle the garlic bulbs on the outskirt of the pan. Set aside.
When handling chicken, contamination safety is the biggest priority. I recommend prepping the chicken in the sink, since it is an easily washable surface and will limit contamination. I place whole chicken in a colander within the larger bowl I used to toss the vegetables to catch all the juices. Remove the bag of innards from the cavity and the pouch located by the neck. I use a gallon ziplock to place all of these items and any chicken discard to freeze and discard on trash day.
Using paper towels thoroughly dry the chicken inside the cavity and out, getting in between the wings and legs. Discard paper towels into your bag with other chicken items. Once the chicken is fully dried inside and out carefully move to a plate.
Sprinkle a bit of kosher salt and freshly ground black pepper inside the cavity ( 1/4 tsp). Place 2 peeled garlic cloves in, 3 thyme sprigs, followed by the peeled lemon, the final garlic clove, and remaining thyme.
Truss the chicken, see notes for step by step of best way to truss a chicken for juicy meat and crispy skin.
Once chicken is trussed, carefully place it on top of the bed of vegetables. You may have to move a few vegetables to ensure it sits evenly on top. Thoroughly wash hands.
Brush a thin layer of lemon juice on the chicken followed by kosher salt and ground black pepper all over the breast and thighs (I use about 1/2 tbsp of kosher salt). Place in the oven.
Roast the chicken for 20 minutes in the oven, carefully remove from the oven and dab a thin layer of olive oil on the skin. I do not baste the chicken after this point, because it will cause the skin to steam, soften, and get chewy. Place back into the oven, dropping the temperature to 425F.
Depending on the weight of your chicken, the roasting time should be about 1 1/2 hour total for a 5lb chicken. For a smaller bird it will take less, so begin checking temperature around 45 minutes-1 hour. This time may also be affected if you use a different trussing technique. I rotate the pan halfway through to ensure even cooking. If you see the garlic bulbs beginning to burn, you can use tongs to flip them over.
The chicken is done when multiple points register at 165F. I test the top front of the breast, back of the breast where it meets the thigh, and the thigh. I test multiple locations to ensure the chicken is fully cooked through.
Once at temperature, remove from the oven and sprinkle chopped thyme over the top. Allow to rest for 10 minutes before cutting. The cavity will have delicious juices inside, so carefully tilt the chicken to empty over the vegetables before moving to a cutting board to slice.
I recommend immediately eating the wings, they are so crispy and your reward for your hard work! To serve, cut the breast in slices with a sharp knife. Serve with the roasted potatoes, carrots, and squeeze out the garlic cloves. Don't forget the pan sauce, it's the best part! Drizzle over the entire plate.