In the human study they didn't use lethicin or cocoa - just heated it in milk and on consumption it caused fusion to occur in the cells they measured it in. So as far as I'm concerned further enhancement of bioavailability beyond this is unecessary.
This is their recipe--
Preparation of the banana shakesFor the C18:0 drink, 24 g of C18:0 intended for human consumption (stearic acid, Sigma-Aldrich W303518) were mixed with 100 ml of low-fat milk. This amount of C18:0 was selected by calculating the C18:0 content of a high fat meal. The mixture was microwaved to emulsify the fatty acid. One small banana was added and the whole mixture was homogenized with a hand blender. The volume was completed to 250 ml with more low-fat milk. The mock drink was prepared the same way without fatty acids. For the C16:0 drink, 21.56 g (an equal molar amount to 24 g of C18:0) of C16:0 intended for human consumption (palmitic acid, Sigma-Aldrich W283207) was added instead. Milkshakes were prepared approximately 90 min before consumption.