Heat a heavy-bottomed skillet over medium heat. Add the bacon to the pan. Cook until crisp, about 5 minutes.
Turn off the heat. Then, using a slotted spoon, remove the bacon. Leave the fat in the pan. Make sure the bacon fat is evenly distributed throughout the pan, and add the onions.
Put the pan on a very low heat and patiently allow the onions to sweat, avoiding any browning at this juncture.
Fold the onions from time to time, allowing them to collapse. They should be very soft. This should take 20 minutes or so.
Add 1/4 cup water to the pan. The moisture from the onions should be sufficient to fully deglaze the pan. Using a wooden spoon, stir and scrape up any fond before transferring the onions to a bowl.
Add the butter to the pan and melt it to the point of frothiness. You'll know when you're there. Low to medium-low heat.
Add the potatoes to the pan and tumble until they are evenly coated in butter. Hit the potatoes with salt. Tumble again.
Raise the heat to medium and cook the potatoes for 15 to 20 minutes, or until they are evenly browned. Lift and turn them occasionally, treating each potato as an equal. Don't flop them about in an indiscriminate mass. That's not cool.
Now, add the garlic and the thyme. Cook for about 3 to 5 minutes, or until the thyme is fragrant and the garlic is toasty-brown.
Add the chicken stock, the onions, and the bacon, and crank up the heat to super-high.
Stir and fold gently while the chicken broth reduces away to a glorious glaze. Turn off the heat about 1 minute before the liquid is fully reduced. Serve.