Combine sugar and 1 cup of half-and-half in a medium saucepan over medium-low heat, whisking until combined. Add remaining half-and-half, heavy cream, and vanilla and cook for 3 minutes.
Meanwhile, in a small bowl, whisk together hot water and gelatin, whisking until gelatin dissolves. Whisk gelatin mixture into half-and-half mixture until thoroughly combined.
Remove from the heat and pour into ramekins or cupcake tins and chill for at least 2 hours or overnight until set.
Remove panna cotta from refrigerator. Dip the bottoms of the ramekins or cupcake tin into a warm water bath for about 15 seconds. Turn out the panna cotta forms onto serving plates. Top with Orange Caramel Sauce and let run down sides. Serve while sauce is still warm.
Melt the butter and brown sugar together in a small saucepan over medium heat. Add the orange juice and star anise and simmer until smooth and thick, about 5 minutes. Stir in the orange zest and remove from heat.