This has been my white whale as it were. I have it on good authority that agar and locust bean gum works but I am not a millionaire and can’t afford locust bean gum.

Here are the directions:
A base recipe as an idea for ratios, 30g sucrose, 49g water, 20g tapioca starch, 1g agar agar.

Mix sugar, agar, and water. Heat to ~90 degrees and mix thoroughly to ensure good agar dissolution. Allow to cool in a water bath at ~40 degrees, keep above agar setting temp and below tapioca gelatinisation temp (~60 degrees).

slowly add tapioca starch (alternative reserve some water initially to make a slurry, you’ll need about 4/5ths the mass of starch, and heat that in the bath to avoid solidifying the agar solution when mixing) stirring well to evenly mix.

Decant into a form, and steam gently over a barely simmering pot for 20 minutes. A vigorous boil will lead to bubbles in the gel.

To achieve layers just steam a layer for ~3 minutes keeping everything to go later in the temp range of 40-60 degrees.