In a large bowl, mix the flour, salt and yeast until combined. Add in the garlic powder and thyme and mix until combined. Next add 3/4 cup grated sharp cheddar (reserving the other 1/4 cup to top the bread). Use your hands to mix together, making sure the cheddar doesn't just clump together in one spot.
Add in the warm water, start with 1 cup and add in the rest a bit at a time. You don't want the dough to be dry, but you don't want it to be wet either. You want the dough to be able to just hold together. It will look a little rough and not smooth.
Cover the dough with plastic wrap and a towel, let sit on the counter for 12 hours, and up to 24 hours).
You want it to have doubled in size. Take a wooden spoon and tap the dough, then give it a good stir which will release some of the bubbles.
Grease your loaf pan and line with parchment paper (this is crucial)
Pour the dough into the loaf pan. Stretch and pull the dough gently to fit the pan. Top with the remaining cheddar cheese. Cover with a piece of parchment paper and a towel and let it rise for another hour or so.
As it's finishing up, it should have risen a slight bit more. Preheat the oven to 400F. Keep the parchment over the dough (so the cheese doesn't get stuck), and cover with tinfoil. Bake for 30 min. covered, then remove the parchment and tinfoil and bake for another 10-12 min until the cheese has melted and started to crisp and the top of the loaf is a nice golden brown.
Remove from the oven and let cool for 10 minutes before you remove from the loaf pan, then let fully cool on a cooling rack.
Slice and serve with butter and if you like a pinch of flaky sea salt. Store on the counter wrapped in a tea towel for 2-3 days. Bread can be frozen but is best if eaten fresh in the first two days.