Bone Marrow Rösti

While traveling in Switzerland I had Rösti a few times. One version used parboiled grated potato (which is traditional) and the other used fresh grated potato. Both were good. The version using parboiled potato had a more pronounced crisp exterior but the natural flavor of the potato seemed diminished.

In the version I had with fresh grated potato the potato flavor was much more pronounced but it lacked a crisp exterior. My version attempts to bridge the gap between the two versions I had in Switzerland.

Bone Marrow Rösti

Chef Way

Using skin-on potatoes and ditching the traditional and time consuming method of parboiling then chilling the grated potato overnight, gives us a same-day version of Switzerland's potato pancake that also swaps butter for bone marrow.

Print Recipe Pin Recipe

Equipment

• 8 inch carbon steel pan
• Fine mesh colander

Ingredients

  

• 4 lbs marrow bones, split lengthwise
• 80 g rendered bone marrow fat*
• 2 lbs waxy potato like Yukon gold
• 80 g rendered bone marrow fat
• 1 % of the weight of the grated potato in pink Himalayan or sea salt
• lemon juice freshly squeezed (to prevent oxidation)
• Black pepper, freshly cracked, to taste
• MSG to taste, (optional)

Recommended Garnishes

• Lemon wedges
• Chives
• Fried eggs
• Smoked salmon
• Butter and flakey salt
• Creme fraiche

Instructions

 

• Preheat oven to 450º F
• Place the marrow bones, marrow side up, on a baking sheet with sides tall enough to hold the rendered fat without spilling. Season them lightly with salt. Roast them in the preheated oven until the bones barely sizzle and all of the fat is rendered into the baking sheet, roughly 30 minutes.
• Rinse potatoes and leave the skin on. The skin has so much potato flavor. Grate the potatoes lengthwise over a large grater. After discard, my yield of grated potatoes was approximately 830 grams.
• Place a nonreactive bowl the grated potatoes will go into on top of a scale. Weigh the grated potatoes by the gram. Next calculate 1% of the weight of the grated potatoes and season the grated potatoes with that amount of salt (e.g. 830 g of potatoes x 1% = 8.3 g of salt)
• Squeeze a bit of lemon juice over the grated potatoes to prevent oxidation. Mix the salt and lemon juice into the grated potatoes thoroughly. Allow the potatoes to rest and release much of their liquid at room temperature covered with plastic wrap for roughly 20 minutes.
• Set up a bowl with a fine mesh colander inside of it to house the drained potatoes. Next squeeze the potatoes by hand thoroughly to remove the majority of their water. However, you do not want the potatoes to be bone dry, as some water is necessary to steam and encourage cooking in the skillet. Place the drained potatoes into a clean bowl.
• Optional step: Pour the potato water out of the bowl you squeezed the potatoes over and harvest the white powdery sludge at the bottom of the bowl. This is potato starch. Scrape this over the grated potatoes and mix thoroughly with a fork before adding the rendered bone marrow. The potato starch will help bind the rösti.
• The marrow bones should be done rendering. Remove them from the oven and reserve 80 g of the rendered bone marrow fat. Pour the bone marrow fat over the grated potatoes and mix throughly with a fork. You want make sure to keep the potatoes light and fluffy as you mix. Next season the potatoes with freshly cracked black pepper and MSG to taste. Gently mix to combine the seasonings.
• Preheat your skillet** over medium-high heat. Carbon Steel or cast iron skillet is recommended in that order.
• Place half the grated potatoes in the preheated skillet. It should be enough potatoes to cover the bottom and provide the rösti with a good amount of thickness. With a rubber spatula shape the rösti’s edges and gently pat down the potatoes to ensure even distribution of potatoes and contact with the skillet. DO NOT press the potatoes down. Doing so will make the rösti dense and hinder even cooking.
• After the rösti is properly shaped and 2-3 minutes have elapsed, lower the heat to medium and cook on that side for around 9-10 additional minutes or until the side is golden and crispy. Proper heat management is key. Too low and you achieve no crisp. Too high and you burn the outside of the rösti and have a raw interior.
• When the first side of the rösti is golden and crispy, use a large plate, cutting board, or pizza peel to flip the skillet over with the rösti in it. After flipping, place the flipped rösti back into the pan over medium-high heat and cook until that side is golden brown and crispy, 8-10 minutes depending on heat management.
• Once complete remove the rösti from the skillet, place it on a cutting board and slice it into triangles. Garnish with your choice of toppings and enjoy.

Notes

*if marrow bones are hard to come by substitute the 80 g of rendered bone marrow fat with melted duck fat, melted butter, or ghee.

**If using stainless steel be sure to properly preheat it over medium-high heat and do the water bead test if unsure that your stainless steel is properly preheated. If you place the potatoes in a poorly preheated stainless steel skillet the potatoes will bind to the pan and prevent you from flipping it without tearing the rösti.

 

The 1% salting of the potatoes is adequate seasoning and provides an agreeable baseline level of salt. We also lightly salted the bone marrow before rendering. If desired you can lightly sprinkle slat in the skillet as I did in the video. Be mindful of the salt levels of your toppings though. Cured salmon, for instance, is salty on its own so try your best to be mindful of your garnishes if you decide to add additional salt to the potatoes in the skillet.