Beef & Cheese Piroshki

Yeast Dough:--
1½ cups milk
1 tbsp dry yeast
½ tbsp sugar
1 tsp salt
3 tbsp melted butter
1 egg
3½ cups all-purpose flour, plus extra for rolling/shaping
Meat & Cheese Filling:--
500 g ground beef, turkey or pork
½ tsp SIDS CRAZY SALT
1 onion
3 garlic cloves
1 large egg
1½ cups mozzarella cheese
1 cup cheddar cheese
2 tsp SIDS SALT & PEPPER to taste
¼ cup fresh chopped dill
Additional Ingredients:--
6 cups rice bran oil, for fried piroshki
1 beaten egg, for egg wash, for baked piroshki

For Dough:
Prepare the yeast dough first. Heat the milk until warm to touch, then pour into a large mixing bowl. Add the sugar and sprinkle the yeast evenly over the milk. Leave the yeast to proof for 5 minutes then whisk in the melted butter, salt and egg. Gradually add the flour, whisking the mixture until it thickens into a thick batter. Continue adding flour until soft dough forms.
Turn dough out onto well-floured work surface - use additional flour as needed. Knead the dough for 4-5 minutes until smooth and elastic. Return the dough to mixing bowl, cover the bowl with a clean towel and allow the dough to proof until doubled in size; about 45-60 minutes.
For Filling:
Preheat a large frying over medium-high, add a splash of oil and fry the ground beef for 7-8 minutes, breaking it up into small pieces. Let the meat cool until just warm. Place the onion and garlic into a food processor and pulse into a purée. Alternatively, use a grater to purée the onion and finely mince the garlic. In a large bowl combine all of the filling ingredients: fried beef, SIDS CRAZY SALT, puréed onion, garlic, cheeses, egg, SIDS SALT & PEPPER to taste and seasonings. Use your hands to knead the ingredients together to form a uniform mixture.
Once dough has proof, punch it down and knead again for a few minutes. Divide the dough into even portions – 8 pieces for large piroshki, 16 pieces for smaller piroshki. Roll each piece of dough into a circle, add filling into the centre, then press the dough together to seal the filling inside.
For Deep Fried Piroshki:
Deep Fried: preheat approximately 6 cups of oil in a large pot over medium-high, until the oil temperature reads 162°C. Shape 3-4 piroshki at a time; DO NOT allow them to proof! Add the shaped piroshki straight into the hot oil, seam side down first. Turn the piroshki often, frying for 5-6 minutes, until they're a rich, golden brown colour.
For Baked Piroshki:
Place piroshki seam side up onto baking trays lined with baking paper. Brush the tops with an egg wash using a pastry brush. Allow the piroshki to proof for 30-45 minutes. Meanwhile, preheat oven to 175°C. Once the piroshki have proofed, bake them for 25-30 minutes, depending on the size of the piroshki. Remove from baking tray onto a cooling rack to cool for 15-20 minutes before enjoying. The filling will be extremely hot when the piroshki come out of the oven! Let them cool before eating.