Upside Down Potato & Onion Tart

This is originally where I got the idea http://hizzoners.com/recipes/vegetables/285-upside-down-potato-a-onion-tart-  but it obviously needs some adjustments because we typically don't eat cheese.  So this is the way I prefer to do it. My husband grew up with a diabetic, so he likes things to be less sweet, which is why I use the yams. Cuts down on the sweetness of the sweet potatoes. For the cheese, I used Yancey's Fancy which you can buy on their website yanceysfancy.com Mine didn't turn out as pretty as the one in the photo, but I PROMISE it is delicious!

2 1/2 Tbl of Kerrygold Butter (it's made with grassfed milk and antibiotic/hormone free)
2 Tbl dried thyme leaves
1 Onion (Cut in thick slices)
1 Yam
1 Sweet Potato
      (Both washed and thinly sliced. If you like the skin on, scrub them before cutting)
2 Tbl Extra Virgin Olive Oil
2-3 Cups Grated Yancy's Fancy Smoked Tangy Applewood (double cream cheddar) It's raw milk cheese.
*Sea Salt and Pepper to taste

Preheat oven to 400°.  Melt the butter in a pan over medium heat and cook the onions and thyme for about 6 mins. While this is cooking, toss the potato slices in a bowl with the Olive Oil, 1 cup of cheese, Salt, and Pepper. Layer onions in a pan, and spread a layer of cheese on top. Put the rest of the potatoes on top of the cheese and put the rest of the cheese on it. If you're like me, you want to make sure just about every inch is coated in cheese :o) Sprinkle some sea salt on top and bake for 45 mins or until golden brown. If you want, you can turn it upside down and attempt to make it look as pretty as the one in the photo of the original recipe lol.

Do it. Your taste buds will rejoice!