For the mac 'n cheese: In a large saucepan, melt the butter over medium heat. Whisk in the flour and cook for about a minute. Whisk in the milk and bring to a boil. Cook, whisking occasionally, for about 2-3 minutes until thickened. Add shredded cheeses and stir to melt. Remove from heat and stir in egg yolks, salt, nutmeg and dry mustard. Stir in macaroni and fold in chopped tomatoes and cooked chopped bacon.