A twist on a classic that includes mushrooms, sweet potatoes, and béchamel.
Many of these steps can be done in parallel.
Step 1: Preheat the oven to 400. Slice the potato and yam thinly. Use a mandoline if you have one. (If using kabocha instead of yam, cut into chunks. It’s fine to leave the thick skin on.) Mix with olive oil in a bowl. Lay on cookie sheets to back in as few layers as possible. Fine to use multiple pans! Bake for ~30 mins at 400, until almost crisp.
Step 2: Peel the onion. Chop it along one axis so that you have large, concentric circles. Add the butter, onions, and some salt to the pan. Stir from time-to-time over medium heat until caramelized, about 30 mins.
Step 3: Wash mushrooms and cut off any black parts on their stems. Melt butter and mix with sriracha. Once fully mixed, add the mushrooms and salt over medium heat. Mix. Cook about 15 minutes, stirring frequently.
Step 4: Warm the frozen spinach in the microwave until lukewarm. Squeeze out as much water as you can.
Step 5: If lasagna plates are not over-ready, boil them according to their packaged directions.
The sauce is a combination of bechamel, crushed tomatoes, and mozzarella cheese.
Step 1: Chop 12 cloves garlic into finely chopped pieces.
Step 2: (Make the bechamel). Heat 6 Tbs butter over low heat until melted. Add the 6 Tbs flour and stir well. Stir constantly for a few minutes until well combined and starting to thicken. Add the chopped garlic. Add 3.75 C of milk, ~1 C at a time. Continue to stir constantly so that the butter, flour, and milk are well combined. Add salt. Heat over low heat for ~5 minutes until thicker. Add 12 oz of rustic cut mozzarella.
Step 3: Stir the 28 oz of crushed tomatoes and 4 oz tomato paste into the bechamel.
Step 1: Set the oven at 375. Chop the mushrooms and onions in smaller pieces so they’re ready to be added in the lasagna.
Step 2: Using a 9x13 pan, begin to layer the lasagna. Start with a layer of plates, then cover it fully with a layer of sauce. Next add the yams and mushrooms (these come first as they’re the biggest pieces). Then add more plates, more sauce, and more veggies. When doing the layer of potatoes, cover with the chopped rosemary. The top layer should be plates covered with sauce. The lasagna plates should be fully covered in sauce so they cook well.
Step 3: Bake in the oven at 375 for 35 minutes. Once it looks almost ready, add the remaining 4 oz of cheese and backe until golden (~5-10 minutes, may have to use broil).