Adjust the oven rack in the upper-middle position of the oven. Preheat to 500°F (260ºC).
In a large mixing bowl (large enough to accommodate the potatoes) mix together melted butter (8 tablespoons), thyme leaves (1 tablespoon), salt (3/4 teaspoon), and black pepper (3/4 teaspoon).
Trim off and save for another use, or discard, ends of potatoes. Cut potatoes (3 pounds) into 1-inch slices. Mix with the butter mixture.
Add potatoes to the butter mixture and toss to evenly coat. Arrange potatoes in a single layer in a 13 by 9-inch baking pan (preferably metal).
Roast in the preheated for 15 minutes.
Remove the pan from the oven and flip over potatoes. Return to oven and roast for 15 minutes.
Remove the pan from the oven again and turn over the potatoes one last time. Pour in chicken broth (1 1/4 cups) with dissolved Better Than Bouillon (1 heaping teaspoon) and garlic (4 cloves). Place back in the oven until potatoes are tender, about another 15-20 minutes, or until bottoms of the potatoes are deeply caramelized.
Spoon sauce over potatoes and sprinkle with remaining thyme (1 tablespoon) serve.
Notes
Unsalted Butter: While using unsalted utter is most important in baking, it's honestly all I buy and have in my kitchen.
Salted butter almost always contains more water than unsalted. The water in butter ranges from 10 to 18 percent. For baking, this is a really big deal. But what do I need added water in any of my recipes? I'm paying for butter, not water!
Fresh Thyme Leaves: Don't use dried thyme. This recipe doesn't have a laundry list of ingredients so each and every ingredient is important to the final taste of these Instagram, Pinterest, and Tick Tock favorites!
Fresh time is redolent with woodsy flavors, with slight lemon and floral notes. If you grow your own thyme in an herb garden (it's super easy to do and I strongly encourage you to do so!!) be sure to plant English thyme for the standard fresh thyme flavor.
Salt: I typically use sea salt but kosher salt works well too (make sure it's the same grind as table salt so it measures as the recipe is has been tested to. Coarse grind will measure differently).
Black Pepper: I test recipes with "McCormicks pure ground black pepper". I like the finer grind of it. When I season my food I use their coarse grind. No endorsement here just what I use and like.
Fresh Garlic Cloves: Peel and coarsely chop the garlic. Because these potatoes are roasted at a relatively high temperature, you need the garlic piece to be larger than a standard garlic press minces them to ensure they don't burn and turn bitter.