Apple and Onion Stuffed Pork Tenderloin

What a nice fall dish!  I like to grill pork tenderloin, but this stuffed version is cooked indoors in a pan and turns out beautifully.  This recipe comes from Clean Eating magazine.  I wish they'd put their recipes online.  I had to try a few tricks to get it cooked through at the end but the results were delish.

All you need is a pork tenderloin, an apple, two onions and some oil, salt and pepper. 

Thinly slice the onion. 

Heat a little oil in a large pan.

And add the sliced onions.

Let them caramelize for about 15 minutes.

Then thinly slice the apple.  I used a Granny Smith and didn't bother to peel it.

Add the sliced apples to the onions.

Toss the apples with the onions and cook for about 5 minutes until the apples are slightly softened.

Put the onions and apples aside in a bowl to cool slightly.

Now for the pork.  Butterfly it. This sounds more complicated than it really is but you just have to slice  the pork until it's flat.  

Make a slit lengthwise along the edge of the tenderloin without cutting all the way through.

Rotate the tenderloin so the slit is at the top and slice again.

Open up the tenderloin so it's lying flat.

Keep slicing until it's completely laid flat and relatively the same thickness all over.
Confusing? Here are some other instructions that might help.

Once the pork is flat, salt and pepper the inside.

Spread the apple onion mixture over the pork.

And add a little more salt and pepper.

Now you're going to need some string.  Butcher's twine is best.  Cut about six 12-inch lengths.

Now start rolling up the tenderloin.  Roll one long end over.

Then slip the twine under the middle of tenderloin and tightly knot it.

Continue tying the tenderloin at regular intervals to keep the filling inside.  

Cut off the long ends of the string, then salt and pepper the outside of the stuffed pork.

Now heat some more oil in the pan over medium heat and place the pork, knot side down in the hot pan.

Flip the tenderloin a quarter turn. You want to sear all sides but cook it slowly so the inside cooks as well.

Flip again to brown all sides.
Now if you cook it low and slow, you should be able to get the inside cooked.  But you can cut it in half to check how it's doing.  

Mine was still quite pink in the centre so I seared the cut ends as well.

I cut it again and still wasn't quite comfortable with the doneness so I put it back in the pan with a little apple juice just to make sure it was fully cook.  Pork can be a little pink but if it's stuffed like this it's harder to get cooked through.

Finally it was done and I served it up with some sage and rosemary squash.

This was a little more finicky than I expected but the results were worth it.  The caramelized onions and apples give it such a nice, rich, seasonal flavour.