Heat butter in large pan over medium heat.
Add diced onion, bell pepper, and the white parts of the green onions and cook for about 7-10 minutes until the onions are soft and translucent.
Next, add in the meat and stir to combine well. Cook for about 10 minutes or until the meat has browned slightly.
Now, add in the diced green olives and spices - cumin, paprika, crushed red pepper, and salt. Combine well. Let simmer uncovered for about 30 minutes.
Take the pan off the heat, and in the green parts of the green onions. Stir to combine.
Let the filling cool completely before filling the dough. You can place in the freezer or ice bath to speed this up, or the filling can be made the day before and refrigerated overnight.
Preheat oven to 450-500F
Before assembling the empanadas, I recommend draining any excess liquid from the filling. Then, add 1-2 tablespoons of filling in the center of the disc.
Wet the rim of the disc with water and close the dough like a half moon.
Add a pinch of the chopped hard boiled egg on top of the filling.
Use a fork to crimp the edge of the half moon, or see video below for the traditional repulgo method of closing.
Bake on an ungreased baking sheet for 10-12 minutes until browned.
Serve immediately.