Combine first 3 ingredients in a medium saucepan; stir in orange juice until smooth. Bring mixture to a boil over medium heat, stirring constantly; boil 1 minute. Remove from heat.
Beat egg yolks and lemon juice in a small bowl until thick and pale. Gradually stir about one-fourth of hot mixture into yolks; add to remaining hot mixture, stirring constantly. Return pan to medium heat; bring mixture to a simmer, stirring constantly. Simmer 1 minute. Remove from heat. Add butter and orange rind; stir until butter melts. Pour filling into a small bowl; let cool. Cover and refrigerate at least 4 hours or until thoroughly chilled.
I added this to a spice cake (in between layers), but feel it would be better in a raspberry crumble muffin :)
Also, added a pinch of red pepper, thought it leavened out the citrus.