Preheat oven to 350°f and grease a 10-inch cake pan or two 6-inch cake pans.
In a large bowl, beat butter and brown sugar until fluffy, about 2 minutes. Don’t forget to scrape the sides of the bowl. Add eggs, beating until fluffy, about 2 minutes. Beat in vanilla.
In a separate bowl, whisk together flour, baking powder, Instant coffee and salt. Gradually add dry mixture to wet mixture, alternating with the buttermilk. So flour, butter, buttermilk; flour, butter, buttermilk, etc. Just until combined after each addition.
Spread batter into prepared pan. Spoon 2 tbs granulated sugar with the figs or blueberries and then arrange evenly on top of batter. Sprinkle with additional granulated sugar over the surface, if you’d like a more caramelized top!
Bake until golden brown and a wooden pick inserted in center comes out clean, 50 to 55 minutes for a 10-inch pan. And about 25-30 min for a 6-inch pan. Let cool for 20 minutes. Serve warm.