Preheat your oven to 325°F/167°C. Generously butter your loaf pan and line it with parchment paper.
In a medium bowl, whisk together the flour, baking powder and salt. Set aside.
In a stand mixer fitted with a paddle attachment, beat the butter for 1 minute on high speed. It should be smooth and creamy.
Add your sugar and beat on high speed for 4 minutes. You want it to be very light and airy. Add the vanilla extract.
Add your eggs one at a time, beating for 1 minute after each new addition and scraping down the bowl well before each addition.
Add the dry ingredients and beat slowly. As soon as there are just a few streaks of flour, stop the mixer. Pour in your sour cream and beat until just combined. Turn off the mixer and fold it by hand until there are no more pockets of flour or sour cream left
Fold in your chocolate chips gently, but keep a small handful to the side.
Pour the batter into your prepared loaf pan. Tap the loaf pan on your countertop a few times to get rid of any air bubbles. Sprinkle over your remaining chocolate chips.
Bake for 75-85 minutes, a tester should come out clean. After 20 minutes, take out of the pan and let cool completely.
In a small saucepan, bring your heavy cream to a simmer (not a boil!). Place your chopped chocolate in a medium bowl, and pour the heavy cream on top. Leave for 3 minutes. With a rubber spatula, swirl the two together until it is completely smooth. Note, you can also do this in a microwave! Sprinkle over your salt. Let it sit until it is a harder consistency, about 15 minutes. Spread on top of your loaf
Notes
Butter: I use European style butter, like Kerry Gold, in my recipes. This will make your finished bake much creamier and richer.Salt: If you don’t have kosher salt, halve the amount of salt called for in the recipe. 1 teaspoon kosher salt = ½ teaspoon fine salt.Storage: the loaf cake lasts up to 4 days at room temperature, keep it well wrapped. Freezing: slice up your loaf and wrap tightly in plastic wrap. Freeze for up to 2 months. To defrost, take it out of the freezer the night before and let it thaw in the fridge overnight.