Line an 8 by 8 inch pan with aluminum foil.
While the sweetened condensed milk is still in it's can, give it a good stir. Then add the extract, stirring again. Pour 1 cup into a glass measuring cup.
Divide the white chocolate chips into three bowls.
Pour 1/3 cup sweetened condensed milk into the first bowl. Microwave in 30 second intervals, stirring very well after each interval. (Mine only took one minute total.) Be careful not to over heat. Once melted, add the red food coloring. Depending on your brand, you may need to add more than is listed here. Once combined, pour into the 8 by 8 pan and spread out evenly. Put it in the refrigerator.
Repeat the process, though this time do not add any food coloring. Pour the white layer over the red layer.
Repeat the process a third and final time, though this time add the blue food coloring. Very carefully spread over the white layer. Add the sprinkles on top immediately after spreading and press into the top of the fudge.
Let cool completely. Remove from the pan, peal off aluminum foil. Cut into squares and serve or store in an airtight container for up to two weeks, unrefrigerated.