Pinto Bean Fudge

2/3 cup canned evaporated milk
1 1/2 cups cooked pinto beans, strained
1 2/3 cups granulated sugar
1/2 cup nuts, any variety
1 1/2 cups miniature marshmallows
1 teaspoon vanilla extract
1 1/2 cups semisweet chocolate chips

Combine sugar and milk in saucepan. Boil for 5 minutes, stirring constantly. Add remaining ingredients and stir until marshmallows melt. Pour into a 9-inch square buttered pan; cool and cut into squares.