Cut the kernels off of two ears of sweet corn, reserving cobs.
Add coconut milk and sweetened condensed coconut milk to a large pot.
To the milk mixture, add the corn and cobs, bringing to a boil and then reducing to a simmer for 20 minutes.
Remove from the heat, discarding the corn cobs.
Add vanilla extract and cool this mixture slightly before adding to a food processor. CAUTION: hot food expands in a food processor or blender and could cause the top to come off releasing the hot liquids. Take the few minutes to allow the mixture to cool before proceeding.
Puree until smooth. There will still be small bits of corn and you can either choose to strain or leave them in.
Add this mixture to a pre-frozen bowl of an ice cream maker and process to a soft serve stage.
Alternately, you can do this without an ice cream maker. Use a blender to really whip up the mixture then add to a freezer safe pan. Allow to come to a soft serve stage before proceeding.
To Make The Blackberry Sauce:
Add blackberries and sugar to a saucepan over medium heat. Allow it to become bubbly and thick.
Remove from the heat and allow to cool slightly. You can choose to strain this mixture or leave the fruit pieces. Be careful. This mixture is HOT!
Layer about 1/2 of the soft serve corn mixture, topping it with a layer of the blackberry sauce. Repeat with the remaining corn mixture and blackberry sauce. You can use a knife to swirl it around.
It's ready to eat, but if you prefer it to be scoopable, just pop it in the freezer for an hour or two.