I had the opportunity to do that a couple of times this week when I stayed with my nephew while my brother Jim and sister-in-law Amy are in Europe. Lucky for me, Jim and Amy are cooks as well and keep a well stocked kitchen.
My first night at the house I rummaged around to find what sort of protein the freezer had to offer. I found a small pork loin roast and a baggie of what I thought were chicken breasts but turned out to be pork chops. Got those thawed out, ready to use the next evening.
I selected the port roast for our first meal. I butterflied the roast and I'm sorry I didn't take pictures of how to butterfly but it would have taken an extra pair of hands. There are a lot of good You Tube films on how to do it though. Basically, you take a thick, rounded roast and cut it in a way that you can lay it out flat. Once butterflied, I sprinkled it with salt and pepper.
Next I went to work on what I would stuff it with. I found some mushrooms, a half an onion, 2 cloves of garlic and some cilantro. I sautéed the onion in some olive oil until tender then added the garlic, cilantro, mushrooms, and fresh sage leaves. Towards the end of cooking I added the sage that I had roughly chopped.
I let the mushroom mixture cool off before spreading it onto the roast.
Starting at one end, roll the roast up.
One of the pitfalls you might experience when cooking in someone else's kitchen, when they aren't there, is where to find things. I couldn't find the kitchen twine for the life of me and I've seen Jim use it before but had no idea where it was. Rummaging through the drawers I did find this trussing kit.
I tied it up and topped with several sprigs of fresh thyme then gave it a thin rub of olive oil.
I baked it in a 350°F. oven for about 90 minutes until it reached an internal temperature of 160°.