If you don’t have leftover rice in the fridge, steam a cup of rinsed jasmine rice in a rice cooker. When done, loosely spread the rice over a large tray and set aside to cool.
Make the meatballs: in a small, deep frying pan over medium heat, heat a tablespoon of olive oil and fry the finely diced onion until soft, then add the garlic and fry until fragrant, and transfer to a mixing bowl.
To the same bowl, add the pork, beef, cooked rice, carrot, egg, a teaspoon each of sea salt, white pepper, sugar, ground paprika, and allspice, and combine until everything is just incorporated but don’t over-mix. Scoop out half a teaspoon of mixture and microwave it or fry it in a little oil, let it cool, try it, and adjust the seasoning or spices to your taste.
Sift some plain flour onto a small plate and over a large tray and, using a tablespoon and digital kitchen scales, scoop out a spoonful of minced meat mixture and weight it, aiming for around 38-40 g, roll it a few times between your hands to form a round meatball, roll it in the flour, and place it on the large tray. Don’t over-roll: you want the mixture loose. Repeat until you’ve used all the mixture and have around 20 meatballs then slide the tray into the fridge.
Make the mushroom gravy: in a cast iron skillet or large pan over medium heat, melt a tablespoon of butter and gently fry the chopped onion until translucent and soft, then scoop out and set aside.
To the same pan, add another tablespoon of butter, sliced mushrooms, sea salt, black pepper, ground allspice, and two tablespoons of olive oil, then turn up the heat, sauté the mushrooms until soft, then set aside with the onions.
Turn the heat down to low, add the sour cream and cream, stir until warm, slowly adding the beef stock, stirring to combine, then return the onions and mushrooms to the pan, add the mustard, ketchup, soy sauce, and fish sauce, stir to combine, and gently simmer.
To fry the meatballs: in the small deep frying pan over high heat, heat half a cup of vegetable oil until hot, then, using long tongs, transfer 5-6 meatballs to the pan (ensure they’re not touching) and fry until brown, rotating the meatballs a few times until evenly coloured, then transfer them to the mushroom gravy. Repeat, frying the meatballs in batches until all are in the pan.
To finish: add 100 ml sour cream to the gravy, stir to combine, taste, add more salt or spice if needed, then simmer the meatballs on low for ten minutes or so to soak up the flavours. Plate with pasta, mashed potato or crispy shoestring fries, garnish with fresh dill, and serve with sides of gherkins, additional sour cream and a crisp Russian garden salad.