Step #1 Put approximately 1/2 c or so of guava paste in a mixing bowl, beat until the color lightens & the texture fluffs/creams up a bit (as opposed to the dense jelly-paste it starts as).
Step #2 Add in 3-4 ozs.
Step #3 softened cream cheese & a squeeze of lime & beat until smooth.
Step #4 Dump this mixture in a separate bowl then whip approx 1.
Step #5 5 c heavy cream in a bowl until light & fluffy.
Step #6 Fold in the guava-cream cheese mixture, fill a pastry bag & use to decorate ccakes as desired.