Seasoned Pork Tenderloin with a Mushroom Gravy

My five year old daughter, Paige, is quite the little helper in my kitchen.  She wants to be involved in everything and anything that I am doing, especially with my cooking.  And a lot of the times, like if I am stove top cooking, she cannot help.  But, that is ok by her, she finds other ways to still be in the kitchen.  One of them is surveying the inventory in my cabinets and my pantry.  She likes to let me know what we are running low on or what else it is that we should get to make something that she is wanting and so on.  This particular morning of the day that I was to make this dish, I was still mentally torn in how I wanted to prepare and season it, she was inspecting the contents under my kitchen sink.  She is long since past the point of spraying windex in her eyes or drinking draino, so please don't be alarmed at this.  She basically just likes to try and read the labels.  But, she came across two grease jars, which are just old jam or pickle jars that I use to store my run-off grease from my cooking in.  Both of them are labeled for what they each are and kept to the back of the cabinet.  She held both of them up to me and asked with a disgusted scowl on her face what these were.  I then replied very nicely that one of them was for general grease and the other, the other one was bacon grease.  She then asked me why they were separated into two jars and why not just together.  I just smiled and said that the regular grease was just for the garbage can eventually, but that the bacon grease was saved for making magic.

1 1/2 lb. pork tenderloin
McCormick's Grill Mates Montreal Steak Seasoning
1 T. of real butter (I use un-salted for everything since I bake so much-but salted is fine too here)
1 T. of bacon grease (if you don't have any, you could just use more butter)
1/2 carton of large whole white mushrooms (chopped)
1 small clove of garlic (minced)
sea salt and fresh cracked pepper
3-4 T. of all-purpose flour (depending on how thick you like it)
1 1/2-2 cups of water
1 recipe of my Mashed Potatoes
steamed corn

-Preheat your oven to 425*.  Line a 9x13" baking dish with aluminum foil (for mess free-or else you will be soaking forever).  Moderately season all sides of the pork tenderloin, toss it onto the lined baking dish and into your oven to roast for 35-45 minutes (the center should be 160* when it is done).  Meanwhile, on your stove top, you can start your gravy (I started it about 10 minutes or so before the pork tenderloin would be done).  Heat up a large saucepan on medium-high heat with your butter and bacon grease.  Once the oils and the pan is good and hot, toss in your mushrooms and the garlic with a light salt and peppering over them.  Saute for about 2-3 minutes while stirring often.  Stir in your flour to coat and cook on for a minute to 'brown' it.  Then just slowly pour in the water starting with just 1 1/2 cups.  Bring this to a boil while still constantly stirring, throw a light dash of more steak seasoning in with it; continue stirring and cooking until it has thickened up (you can either add in more water to thin it down or not).  Reduce the heat to low and cover the top with a lid.  Once the pork tenderloin is done, remove it from the oven and go ahead and slice it up (no standing time is necessary with this cut of meat).  Serve it with some mashed potatoes and corn with the gravy over everyone!  Serves 4.  Enjoy!