In sauce pan, dissolve brown sugar and water over low heat until color turns to pale brown (do not stir just swirl the pan gently). Cover the bottom of each loaf pan with the caramel.
In a mixing bowl, combine the egg yolks, condensed milk, evaporated milk and vanilla. Use whisk to mix gently, prevent bubbles from forming. Remove any solids by using a strainer. Pour the mixture on top of the caramel in the loaf pans. Fill the pans to about 1 to 1 1⁄4 inch high.Cover loaf pans with an aluminum foil. Place rack in bottom of CanCooker and add 24 oz water. Place loaf pans on top of the rack. Cover and latch lid. Steam for about 40-45 minutes. Remove the loaf pans and let it cool at room temperature then refrigerate for several hours before serving.
Flan is cooked when a knife is inserted in the center of the loaf pan and comes out clean. To remove the flan from the loaf pan, run a thin knife around the edges of the loaf pan to loosen the flan. Place a platter on top of the loaf pan and quickly turn upside down to position the golden brown caramel on top.