Prepare your square 8x8 or 9x9 inch pan with cooking spray and parchment paper. I always end up cutting all around the edges of the parchment paper so I can get it into the fridge easier to set after I pour fudge into it. Set aside.
Get out and organize your ingredients. Measure anything you want to add into the fudge or on top of it so everything is ready to go!
In a saucepan, over low heat, warm condensed milk until hot but not boiling.
Add chocolate and white chips and food coloring.
Stir frequently until melted, smooth and incorporated. If necessary to smooth out add 1 to 2 tablespoons of butter or shortening to assist in the melting process!
Stir in flour until blended.
Once flour is incorporated, add any ingredients you want to your fudge. Just remember the fudge is hot so if you are adding sprinkles, for example, add them to the mixture, stir two or three times and dump into your prepared pan. You don't want your ingredients to melt.
Pour into a square 8x8 inch lined pan, add or sprinkle anything you want to stick to the top of the fudge and set aside.