Preheat the oven to 450 degrees F.
Place the potatoes on a cutting board. With the tip of a small, sharp knife, score a lid shape on the top of each potato about a third of the way down, cutting in about 1/8 inch all the way around.
Spread a 1/4-inch-thick bed of rock salt on a baking tray. Place the potatoes on the bed of rock salt. Bake the potatoes until tender enough to be pierced easily with a wooden skewer, about 45 minutes. Remove the baking sheet from the oven and leave them for a few minutes to cool slightly. Leave the oven on.
Heat a saute pan over high heat. Add the olive oil and, as soon as it swirls easily, add the butter. When the butter foams, add the ham and mushrooms and saute until they are hot, 2 to 3 minutes. Transfer the ham and mushrooms to a small mixing bowl.
Using a small, sharp knife, and protecting your hand from the heat with a folded kitchen towel, carefully cut off the lids from the still-hot baked potatoes, following the scoring marks. With a sharp-edged tablespoon, scoop the flesh from the potatoes, including the lids, leaving a wall about 1/4-inch thick, and transferring the scooped-out flesh to a large mixing bowl. Return the potato shells and lids to the bed of rock salt. Put the tray back in the hot oven, leaving the oven door open, to keep the potato shells and lids warm.
With a potato masher, mash the potatoes. Season the mixture, to taste, with salt and generously with pepper. Add the creme fraiche or sour cream and the butter and mash to combine them with the potatoes. Stir in the ham, mushrooms, and 2 ounces of the cheese.
Remove the baking sheet from the oven and turn the temperature up to 500 degrees F.
Carefully spoon the mashed potato mixture back into each potato shell. Sprinkle the remaining cheese on top of the filling on each potato. Leave the lids unfilled, placing them around the side of the tray.
Return the tray to the oven and continue baking the potatoes until they are heated through and the cheese has melted, 7 to 10 minutes. If the cheese has not browned, turn on the broiler and broil the potatoes briefly, keeping a close eye on them to prevent burning.
Using tongs, transfer the potatoes to a heated serving platter or individual plates. Place the lids on top of the potatoes at an angle, inserting 1 end partway into the filling to secure them.

Kitchen-Friendly View

Nutrition Facts

Per Serving Per 100 g

Amount Per 1 Serving
Calories	326.04 Kcal (1365 kJ)
Calories from fat	233.38 Kcal
		% Daily Value*
Total Fat	25.93g	40%
Cholesterol	68.12mg	23%
Sodium	473.49mg	20%
Potassium	154.77mg	3%
Total Carbs	3.61g	1%
Sugars	0.58g	2%
Dietary Fiber	0.19g	1%
Protein	19.17g	38%
Vitamin C	0.8mg	1%
Vitamin A	0.1mg	2%
Iron	0.2mg	1%
Calcium	393.7mg	39%

Amount Per 100 g
Calories	280.8 Kcal (1176 kJ)
Calories from fat	201 Kcal
		% Daily Value*
Total Fat	22.33g	40%
Cholesterol	58.66mg	23%
Sodium	407.79mg	20%
Potassium	133.29mg	3%
Total Carbs	3.11g	1%
Sugars	0.5g	2%
Dietary Fiber	0.16g	1%
Protein	16.51g	38%
Vitamin C	0.7mg	1%
Vitamin A	0.1mg	2%
Iron	0.2mg	1%
Calcium	339.1mg	39%

* 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

Search recipes
by ingredients

Construct & Analyze
Your Recipe

Analyze

Try this similar recipes

Chef John's Chicken Cacciatore

Olive oil, Whole roasting chicken, cut in quarters and 13 more..
Beef Sliders Stuffed with Walnuts and Gorgonzola

Olive oil, Bacon, finely chopped, Chopped shallots and 9 more..
Veal Chops With Mushroom Sauce

Olive oil ., Minced onion, Minced celery, Minced mushrooms and 8 more..
French Onion Dip Pizza

Extra virgin olive oil, plus extra for brushing and 10 more..
Spinach Mushroom Strata

Frozen spinach, thawed, Unsalted butter and 11 more..
Mushroom Onion Gruyere Tart

Canola oil, Butter, Sweet onion (sliced ) and 8 more..
Bistro Onion-Jalapeno Pizza

Onion (halved then thinly sliced, or use as many as desir... and 11 more..
Mushroom Lasagna

Boiling water, Olive oil, Onions, Garlic cloves, minced and 13 more..
Bourbon Street Steak

Top sirloin steaks, Worcestershire sauce, Soy sauce and 18 more..
Vegetable Manicotti

Garlic cloves, minced, Olive oil and 11 more..
Fresh Vegetable Tian

Olive oil, divided and 10 more..
Chicken Fricassee (Fricassée De Poulet)

Butter, Olive oil, Onion, peeled and chopped and 11 more..