Beat cream cheese and butter on medium speed until light and fluffy, about 5 minutes.

Add 4 tablespoons of milk and vanilla bean seeds (or vanilla bean paste or vanilla) beat again for 2 minutes.

Gradually beat in powdered sugar. Beat until light and fluffy. If too thick add a bit more milk, just a teaspoon at a time. If too thin add a bit more powdered sugar. (It needs to be thick enough to hold its shape, but not so thick that you have difficulty swirling the icing through the decorating tip.)

Prepare icing as directed and divide into two or three bowls, depending on how many colors you want in your swirls. Add food coloring to achieve desired colors. I really like the gel food coloring, it gives much deeper, richer colors and comes in a wide variety of beautiful hues.

Lay out 2 or 3 (depending on how many colors you are using) pieces of plastic wrap (approximately 18"-20" long) on your work surface. Spread out the contents of each bowl on a separate piece of the plastic wrap lengthwise, forming a rectangle, approximately 8" long. Starting with one long side, fold plastic wrap over the icing and roll into a cylinder-shaped tube. Secure both ends with a knot. Repeat with the remaining colors.

When you're ready to ice the cupcakes, fit a large pastry bag with a large star decorating tip. (I use a Wilton 1M) or snip a tiny corner off of a gallon-size zippered bag and fit with a large star decorating tip.

Cut off one of the knot ends from each tube and place tubes in prepared pastry bag. Pipe cupcakes as desired. Have fun watching the three beautiful colors unfold!