Dough
Mix the flour and salt in a bowl, add sugar, egg, oil, and water. Blend with a hand mixer until dough comes together.
On a lightly floured surface roll out the dough into a thin sheet and cut out round disc shapes for empanadas.
Use the empanada discs immediately or store in the refrigerator or freezer until ready to use.
Filling
Heat 1 tablespoon oil in a large pan over high. Cook beef, breaking up with a spoon, until browned but not completely cooked through, 6–8 minutes. Transfer to a medium bowl with a slotted spoon, leaving as much fat in pan as possible.
Reduce heat to medium and cook onion in remaining 1 tablespoon oil, stirring, until tender but not browned, 6–8 minutes; season with salt and black pepper. Add cumin, paprika, oregano, and cayenne and cook, stirring, until fragrant, about 1 minute. Add chicken stock and reserved beef along with any accumulated juices to pan. Bring to a simmer and cook, stirring and scraping up any brown bits, until most of the liquid is evaporated, 15–20 minutes; taste and season with salt and black pepper, if needed. Transfer to a medium bowl, cover, and chill at least 3 hours.
Heat oil in a deep fryer or deep pot filled with oil until hot. Place a slice of hard-boiled egg and a large spoonful of filling in the center of each round. Top with a sprinkle of pine nuts. Brush water around half of the outer edge of each round. Fold round over filling and pinch edges to seal. Using a fork, crimp edges.
Fry empanadas until crispy, remove to drain on paper towels. Serve hot with tomato dip.