Thinly slice the steak. Then chop into bite site pieces.
Place the steak in the Instant pot.
Add half the onions to the pot. Save the rest of the onions in a small bowl.

Meanwhile season with salt and pepper.
Pour the beef stock over the beef.
Squeeze the juice of two fresh limes over the meat and onion mixture.
Lock the lead on and make sure the valve is set to sealing.
Set the pressure to high pressure for 15 minutes.

While the steak is cooking, melt the butter in another skillet
Fry the mini corn tortillas in the melted butter for 1 minute until they are soft.
Allow them to cool slightly.
You will need 2 mini corn tortillas per taco.
Once the pressure is up do a quick release, and stir.
Spoon the meat mixture on the tortillas.
Top with cilantro, fresh onions and serve with limes.

Notes- this is the steak i used i couldn't find the other steaks, so i got the cheapest steaks... and i seasoned them before i put them in the instant pot. i did lay the meat on top of each other as you can see in the pictures. I didn't cut mine i will be shredding it after it has cooked, in a food processor.