First, the caramelized onions:.
IN EACH STEP, YOU WILL NEED TO STIR ABOUT EVERY 10-15 MINUTES, UNLESS OTHERWISE NOTED.
Cut off stem and root ends of onions, and peel away the dried skin. Slice into 1/4 slices adn gather in a large, heavy bottomed pot. A 7 qt pot works perfectly.
Pour the oil and salt over onions and toss to combine. (NOTE: Because I fried bacon to use for the dish, I used 2 T of the bacon fat, and then added veggie oil to make up the 1/2 Cup. Gave a great other layer of flavor to the onions) Set over medium heat and cover. Cook until onions begin to wilt, for 20-30 minutes. (Don't forget the stirring!)
Reduce heat to low and continue cooking, with pot still covered, for 45 minutes. (are you still stirring?).
Remove the lid, increase heat to medium and cook (stirring) 30 minutes, or until most of moisture has evaporated.
Reduce heat to low and continue cooking for about 2 hours, stirring every 20 minutes.
Continue cooking and stirring for about 1 more hour. You'll need to watch more carefully now, stirring about every 10 minutes. Cook until onions have been reduced to a deep reddish-brown marmalade, watching that they do not dry out. When done, removed from heat and set aside to cool.
-.
Slice potatoes as thinly as possible (a V-slicer works great). Place potatoes in a 3 qt heavy bottomed pot or saucepan and add milk, cream, garlic, salt and bay leaves. Cover and bring ust to a gentle simmer, then remove lid and cook until potatoes are firm but tender, 15-20 minutes.
Heat oven to 375 and put a large cookie sheet on bottom rack to catch drips. Position another rack in center of oven.
Rub inside of large gratin dish with generous amount of butter. Using a slotted spon, transfer about half of the potatoes to the dish, in an even layer. Stir together caramelized onions and bacon/prosciutto adn distribute evenly on top of potatoes (should be enough for a very thin layer). Top with 1/4 of the cheese.
Put the remaning potatoes in the dish, smooth to an even layer and pour cooking liquid on top. I like to shake on a good dusting of white pepper, but this is optional. Scatter the remaining cheese over the top and bake until top is bubbly and evenly browned.
Let sit for about 10-15 minutes before serving.

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Nutrition Facts

Per Serving Per 100 g

Amount Per 1 Serving
Calories	514.59 Kcal (2154 kJ)
Calories from fat	391.64 Kcal
		% Daily Value*
Total Fat	43.52g	67%
Cholesterol	28.65mg	10%
Sodium	820.44mg	34%
Potassium	456.94mg	10%
Total Carbs	22.88g	8%
Sugars	4.3g	17%
Dietary Fiber	4.56g	18%
Protein	10.11g	20%
Vitamin C	4.8mg	8%
Calcium	327.9mg	33%

Amount Per 100 g
Calories	147.45 Kcal (617 kJ)
Calories from fat	112.22 Kcal
		% Daily Value*
Total Fat	12.47g	67%
Cholesterol	8.21mg	10%
Sodium	235.09mg	34%
Potassium	130.93mg	10%
Total Carbs	6.56g	8%
Sugars	1.23g	17%
Dietary Fiber	1.31g	18%
Protein	2.9g	20%
Vitamin C	1.4mg	8%
Calcium	93.9mg	33%

* Percent Daily Values are based on a 2000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.
Find out how many calories should you eat.

Tastes

salty
savory
bitter
sweet

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