in mixing bowl, combine sour cream, softened cream cheese, cream of mushroom soup, alfredo sauce and 1 cup of cheese.
in skillet saute pureed tomatoes with chili's, onions, celery, seasonings with 1/2 stick butter add seasonings, then add crawfish, saute for approx 1 min. add shrimp and crab after draining them. add rest of butter. get the mixture hot to allow butter to melt. remove from heat.
layer in pan, thin layer of sauce mixture, 1 layer of noodles, spread seafood mixture then sauce, noodles, seafood sauce and so on till top is sauce then top with cheese. be sure to place a sheet pan under your lasagna pan as this tends to bubble up and sometimes overflow. cook 1 hr at 350 degrees. let cool for easier eating.