Preheat oven to 375° F, and lightly oil a baking dish with 2 teaspoons of olive oil.  

In a large saucepan, melt butter over medium heat and add fennel, onion and garlic until the combination becomes fragrant and transparent (around 5 minutes). Incorporate tomato paste into the mixture. Add oregano, basil, salt and pepper, then continue to cook for an additional two minutes.   

Add the Italian sausage to the pan and break apart the meat with a spatula until entirely cooked and browned. Pour in the crushed tomatoes, sugar and crushed red pepper flakes. Raise the temperature just slightly so the meat sauce bubbles gently. 

In a separate saucepan, prepare the bechamel. Melt butter over medium heat, then whisk in the flour until the texture resembles a thin paste. Adding a small amount at a time, begin to add the milk to the mixture until all the milk is in the pan, whisking continually the entire time.  The bechamel should resemble a gravy. Sprinkle in the garlic powder, cayenne and nutmeg and whisk one more time before setting aside over low heat.  

Grab your baking dish and spread a thin layer of the meat sauce evenly over the bottom of the pan to prevent the noodles from sticking.   

Lay three noodles down covering the meat sauce, then top with a healthy drizzle of bechamel sauce and cover with a thick layer of shredded mozzarella. Start the second layer of lasagna noodles, and top with meat sauce. Lay down a third and final set of noodles, and drizzle on the bechamel and shredded cheese. 

Cover top with aluminum foil and bake for 40 minutes. 

 After 40 minutes, set your oven to broil, sprinkle with the shredded mozzarella and chives, remove foil, and finish the dish under direct heat so the cheese turns golden brown.