Prepare your pressure canner, jars, and lids:
Heat the olive oil in a heavy bottomed skillet. Lightly saute ½ cup of the onions just until translucent.
Add 2 pounds of the ground meat, and stir to break it up. Cook, stirring, until just browned. Don’t cook it all the way. It will continue to cook during processing.
Mix in 4 Tablespoons of the taco seasoning. Use a slotted spoon to remove the mixture from the pan and put into a large bowl. Repeat for the rest of the onions and meat.
Start filling each jar with the taco meat mixture. Don’t pack it in tightly, but don’t leave big gaps either. Make sure you leave 1 inch of headspace.
Now, fill the jar with boiling water, again, leaving 1 inch headspace. Remove trapped air bubbles and top off with water if necessary, leaving 1-inch headspace.
Clean rim of jar. Put on lid and screw band. Place in canner. Repeat for remaining jars.
Process pint jars for 75 minutes at 10 pounds of pressure, quart jars for 90 minutes at 10 pounds pressure.
Always check the Altitude Adjustment Chart before you start so you know what your pressure needs to be!
After processing, turn off the heat and allow the canner to cool off and the pressure to return to zero.
When the pressure has returned to zero, carefully remove the jars with the jar lifter. The jars will still be extremely hot and the contents will be boiling.
Put your jars on a towel lined cabinet and leave them undisturbed for 12 to 24 hours. After 12 hours you can check the seals.
If all the jars are sealed, remove the rings, wipe down the sides of the jar, and label and date the contents. Now store them in your pantry in a cool, dark place.
The meat is already cooked, so all you have to do is heat it up. And that makes dinner so much faster to get on the table!