Sprinkle sugar in a heavy skillet. Cook over medium heat, stirring constantly with a wooden spoon, until sugar melts and turns light brown. Remove from heat. Quickly pour hot caramel into a 9" round cakepan, tilting to coat bottom; set pan aside. (Caramel syrup will harden and crack.)
Combine eggs and remaining 7 ingredients in a large food processor or blender. Process just until smooth, stopping once to scrape down sides. Pour custard mixture over syrup in cakepan. Place cakepan in a large shallow pan. Cover cakepan with aluminum foil. Add hot water to shallow pan to depth of 1". Bake at 350° for 50 to 55 minutes or until knife inserted off center comes out clean. (Center should still be slightly liquid; flan will finish cooking as it cools.)
Remove cakepan from water bath; cool flan completely on a wire rack. Cover and chill several hours or overnight. Loosen edges of flan with a spatula, and invert flan onto a rimmed serving plate, letting caramel sauce drizzle over the top.
Note: We found that a large food processor worked best for blending this flan. Otherwise we recommend using a blender.