Bake tarts according to package directions. Cool and set
Wash and thinly slice the Nergi kiwi berries. Set aside 2/3 of the berries, and finely chop the remaining berries. Set the slices apart from the chopped berries.
In a small bowl, stir together mascarpone, coffee and sugar until combined. Mix in chopped berries. This can be done in advance and stored in the refrigerator (in an airtight container) until ready to assemble.
When you are ready to serve, assemble your tarts. Lightly layer one slice of Nergi on the bottom, then equally divide the mascarpone mixture, and top with more slices of Nergi to create a pretty finish.
To make the garnish, melt the chocolate chips and whisk with whipping cream to combine. Drizzle over the tarts. Enjoy promptly.