How to Create Smoothly Rounded 3D Embossed Shapes in Fusion 360?

[kaan]

Hello friends. I want to create a mold in Fusion, but I'm not entirely sure how to do it. In the image with the balloon, you can see that the balloon shape appears raised and smoothly rounded on the dough. To achieve this, the 3D embosser we design must be the inverse of that shape. However, I'm struggling to figure out how to give the embosser that curvature and apply it in the best way for different shapes. For example, I tried making a heart shape in the photos. I cut the body by 1-2 mm using the heart shape and then softened the edges with fillet, but the center remains flat. What is the best way to make it rounded? This question applies not just to the heart but also to a balloon, or maybe something like the letter "K" or another shape. What is the technically correct way to draw it so that it comes out fully rounded?

[TrippyLighting]

The technique would be different for the heart, the balloon and the letter K.

The heart I'd probably to with a T-Spline. The balloon could be a revolved shape that could then be scaled non-uniformy.

The letter K is probably a mixture of techniques, possibly also T-Spline.