Pre-heat oven to 350°F.
Generously season top sirloin steaks with salt and pepper.
Add oil to a cast iron skillet and heat on high until hot.
Add the medallions and sear both sides. Make sure to roll the edges so they get a nicely caramelized crust.
Place steaks on wire rack on a baking pan.
Place in oven and cook the steak until probe thermometer reaches 48°C, about 5-10 minutes.
Remove the steaks from the oven, flip over, and let rest on a new rack in a warm place while you finish cooking.
While the steaks are resting, season the shrimp with salt and pepper.
Heat 2 Tbsp. butter until bubbly in the cast iron pan used for cooking the steaks.
Add the shrimp and cook the shrimp for about 1 minute per side until done
Remove shrimp from the pan and add 2 tbsp of butter and the mushrooms.
Sauté until caramelized, push mushrooms to one side of the pan, and in the open space add the garlic and toast.
Toss garlic into the mushrooms and then deglaze with white wine.
Cook the wine until almost gone and then add the cream. Reduce the cream until sauce consistency.
Season with parsley, salt and pepper.
Add the shrimp back to the mushroom sauce.
To plate, put steak onto plate and smother in the creamy garlic shrimp and mushroom sauce.