In a small pan, combine water, 1/2cup sugar and mint; bring to a simmer, stirring occasionally to help dissolve the sugar. Let simmer over low heat to steep the mint. Strain the mint from the simple syrup. Discard the mint.
Combine 2cups of chopped strawberries with remaining 1tbsp of sugar in a food processor. Puree the strawberries.
Add mascarpone cheese, lemon juice and salt. Run the machine until the cjeese is completely incorporated.
Add the mint simple syrup and process to combine.
Place the strawberry mixture in an 8" glass dish and place the dish in the freezer.
The mixture will take about 4 hours to freeze.
When ready to serve, use a fork to scrape the granita. Spoon the mixture into serving bowls and top with the finely chopped strawberries and serve immediately.