Whether found in the sandbox, under the bed or in Nana's closet (which is where we "found" ours!), Legos are KILLER to clean by hand. Think toothbrush and lots of soaking time. But if you have a dishwasher and a lingerie bag from your laundry room - WAY simpler!
It might take a while to dry because they get water trapped inside but they come out SQUEAKY clean and makes for a very, very happy Mama!