In a large saucepan, combine sugar, milk, vanilla, butter and espresso powder.

Bring to a boil over medium high heat, stirring constantly.

Once boiling, keep at a rolling boil for two full minutes (still stirring).

For this next step, I use a stand mixer with whisk attachment, but a hand mixer would work too.

In a large bowl, combine marshmallows and chocolate.

Pour hot mixture over these ingredients and blend until smooth. I turn my mixer on medium speed and allow it to blend for about 2-3 minutes, scraping down the sides of the bowl several times.

While this is mixing, place your caramel and heavy cream in a microwave safe bowl and heat for 1-2 minutes, stirring every 30 seconds until melted and smooth. Set aside.

Pour the creamy fudge mixture into a parchment paper lined 15inch x 10inch x 1inch baking sheet. Drizzle with hot caramel, using a knife to swirl it into the fudge.

Sprinkle immediately with kosher salt (or coarse sea salt).

Refrigerate for 4 hours, or overnight.

Cut into small bites and store in the refrigerator for up to two weeks. ENJOY!