In a medium bowl, add the dried morels and cover with boiling water. Place a plate over the bowl to cover. Allow to steep for 30 minutes.
In a small saucepan add the quinoa and water and bring to a boil. Reduce heat to low and cook for 10-15 minutes or until quinoa is cooked and water has been absorbed. Fluff with a fork and set aside.
Preheat oven to 400F.
In a large oven-proof skillet, add the olive oil and swirl the pan to coat. Add the shallot and saute over medium-high heat until is just beginning to get soft, about 5 minutes. Add the spinach, 2/3 of the cooked morels (reserve the liquid) and rosemary and saute until the spinach just wilts, about 2 minutes longer. Remove from heat and add to a large bowl. Toss in the cooked quinoa and set aside.
Lay the flank steak on a large cutting board and cover with plastic wrap. Use a meat mallet and pound the flank steak to flatten to a 1/2 inch thickness. Flip the steak over and cover with the wrap again and continue to pound a few more times. Spread a layer of the quinoa mixture over the flattened beef and roll up like a jelly roll. Use kitchen twine to secure.
Heat the large skillet again with 2 tablespoons of olive oil over high heat. Add the beef and sear on all sides. Move the skillet to the hot oven and bake for 15-20 minutes. Remove the beef from the skillet and allow to rest, covered in foil, on a cutting board.
Place the skillet back over a high heat and add the bourbon and morel cooking liquid. Use a wooden scraper to dislodge all of the bits on the pan and boil for 5-7 minutes to reduce the liquid by half. Add in the remaining 1/3 baby morels and remove from heat.
Slice the beef and place on a serving platter. Pour the pan jus over the top and serve.