Stem and slice the peppers. If a couple of seeds remain on the flesh, it's not a big deal but try to remove most of them as they tend to burn quickly in the hot oil.
In a skillet, heat oil to high and saute the sliced peppers until they start to collapse, about 3 - 5 minutes.
Add the sliced onion and salt then saute until the onions get a glassy / translucent look for about 3 -5 minutes.
Remove the vegetables and add the slices of meat and salt.
Sear the meat on one side until golden brown then flip it over after 3 - 5 minutes.
Sear the other side too until golden brown for 3 - 5 minutes.
Mix the onion and pepper back then top it with the diced garlic and paprika or chili. Saute for 5 more minutes then remove from the heat and let it cool off.
Serve it on corn tortillas, flour tortillas or just have it on its own.