In a medium saucepan, heat cream, coconut milk, and ¾ cup sugar over medium heat. Stirring constantly, let mixture reach just the point of simmer and remove from heat.
Lightly whisk egg yolks in a separate bowl.
Slowly pour about half of the warm cream/milk mixture into the bowl with the yolks, whisking continuously. Then pour egg/coconut milk mixture back into the saucepan with the rest of the milk.
Continue to cook over low heat, while still whisking. When the mixture thickens enough to coat the back of the spoon, after about 5-7 minutes, remove the saucepan from heat.
Strain cream mixture into a bowl and cover with plastic wrap so that plastic is touching top of cream (this will prevent a skin from forming). Refrigerate until chilled, at least 5 hours.
Right before processing ice cream, mix strawberries and blueberries with the remaining 2 Tbsp sugar and let sit for about 15 minutes.
Once cream mixture is chilled, freeze in an ice cream maker according to the manufacturer’s instructions. When ice cream is almost frozen, mix in vanilla, strawberries and blueberries and marshmallow fluff.
When ice cream is frozen, remove to airtight containers and place in freezer for at least 4 hours to continue to harden.