Add <quantity>1<unit>cup</unit></quantity> of apple cider vinegar and <quantity>1<unit>cup</unit></quantity> of water to a large pot over high heat

Add <quantity>½<unit>cup</unit></quantity> of white sugar

Add <quantity>1<unit>tbsp</unit></quantity> of salt and mix. Bring to a boil and remove from heat

Place <quantity>200<unit>g</unit></quantity> mustard seeds in a large, sealable jar

Fill the jar with the hot brine. Seal it and turn it upside down to create a vacuum. Let it sit for 3d. The pickled mustard seeds are ready

Season a <quantity>300<unit>g</unit></quantity> piece of pork belly with salt and sugar to taste

Place the pork belly in a deep baking pan and place it in the refrigerator for at least 12h to lightly cure

Add <quantity>500<unit>g</unit></quantity> of portobello mushrooms to a blender

Add <quantity>10<unit>g</unit></quantity> of salt and blend on medium speed until it becomes spreadable

Evenly spread the mushroom paste on a baking sheet

Leave the mushroom paste uncovered at room temperature until it turns black. Stir from time to oxidize in an uniform way. The preserved mushroom spread is ready

Place <quantity>500<unit>g</unit></quantity> of all-purpose flour and <quantity>2</quantity> pinches of salt in a stand mixer bowl

Add <quantity>200<unit>g</unit></quantity> of sour cream and <quantity>100<unit>g</unit></quantity> of softened butter

Add <quantity>2</quantity> eggs

Add <quantity>¼<unit>cup</unit></quantity> of water. Mix on medium speed until you get a smooth dough

Add <quantity>2<unit>tbsp</unit></quantity> of all-purpose flour if the dough is very wet and sticky. Mix on medium speed until well incorporated

Dust a work surface with all-purpose flour

Dust the dough with flour and knead for 5m until smooth. Form a tight ball

Transfer the dough to a container and cover with a kitchen towel. Place in the refrigerator for at least 1h to relax

Place <quantity>800<unit>g</unit></quantity> of lard in a saucepan over medium heat. Warm until it begins to bubble. Turn off the heat

Carefully pour over the pork belly

Soak a sheet of parchment paper in water

Squeeze out the excess water and cover the pork belly with it

Cook the pork belly in the oven for 2h until crispy and golden brown. Be careful when removing from the oven to not splash the lard. The crispy pork belly is ready

Place <quantity>2</quantity> pots in a large container. Fill one with hay and the other with <quantity>1<unit>cup</unit></quantity> of sour cream

Light the hay with a blowtorch and cover the pots with another container, or aluminum foil, to seal. Leave it for 5m until smoked

Season the smoked sour cream with salt to taste

Add lemon juice to taste and stir to combine and loosen

Transfer the sour cream to a piping bag and set aside

Place <quantity>800<unit>g</unit></quantity> of lard to melt in a large saucepan on medium heat until it reaches <temperature>170<unit>°C</unit></temperature>

Remove the dough from the refrigerator. Cut off about a quarter and flatten it by hand

Pass the dough through a pasta machine. Fold in thirds and pass at the same thickness 3 times, to get a <quantity>5<unit>mm</unit></quantity> thick sheet. Repeat with the remaining dough

Dust both sides with all-purpose flour and punch <quantity>10<unit>cm</unit></quantity> diameter disks

Fry the disks until puffed and golden brown, flipping from time to time for even cooking

Transfer to a tray with kitchen towels to drain. The schmalzgebackenes are ready, enjoy!!!

Chop the Crispy Pork Belly

Melt <quantity>1<unit>tbsp</unit></quantity> of butter in a large pan over medium-high heat

Add <quantity>1<unit>cup</unit></quantity> of green kale leaves and season with salt to taste. Sautée until bright and tender

Spread <quantity>1<unit>tbsp</unit></quantity> of the Preserved Mushroom Spread on a Schmalzgebacken. Top with kale to taste

Top with the smoked sour cream to taste and <quantity>1<unit>tsp</unit></quantity> of the Pickled Mustard Seeds

Shave mushrooms to taste with a truffle shaver or peeler. Top with the Crispy Pork Belly. The schmalzgebackenes with pork belly is ready

Enjoy this fun and savory dish!