Preheat oven to 375 degrees. Spray a 9x13 baker with non-stick spray and set aside.
Peel 5 pounds of golden potatoes. Slice thinly with a knife, mandolin, or make short work with a food processor.
Place potatoes in a pot and cover with water. Salt. Allow to come to a boil.
While potatoes are boiling, shred your cheese.
Once potatoes come to a boil, lower heat to a simmer, and allow to cook 5 minutes, or until just tender.
In a large microwave bowl, microwave your cream cheese so it softens and begins to melt. This should take 1 to 1 ½ minutes.
Once the cream cheese is very soft, stir in the milk, cream, garlic & onion powders.
Pour a tiny bit of this cream sauce into the bottom of your baking dish.
Drain your potato slices.
Add ½ of the potatoes slices to your baking dish. Pour over ½ your cream sauce, sprinkle ½ of your jack cheese, bacon and jalapenos on this layer (the rest is for the top!).
Repeat the previous step. Basically you made a 2 layers.
Cook for 30 minutes in your preheated oven. You dish should be golden on top, and the sauce should be bubbly. Allow to sit and rest for 5 minutes and then serve!