Preheat the oven to 350F. Grease and line a standard (9x5”) loaf pan with parchment paper; set aside.

Add the ½ cup butter to a saucepan over medium-high heat. Allow to melt and slightly brown (~5 minutes). Remove from the heat and immediately pour into a large bowl. Set aside to cool slightly.

In a medium bowl, combine the flour, cinnamon, both sugars, and butter. Mix until it resembles wet sand. Then, mix in the chocolate chips. Place into the refrigerator to chill while you make the rest of the loaf cake.

In a medium bowl, whisk together the flour, baking powder, and salt. Set aside.

Once the brown butter has slightly cooled, add the sugar. Whisk until well combined.

Add in the eggs, and whisk until fully incorporated.

Then, add in the greek yogurt, milk, and vanilla. Whisk until well combined.

Add the dry ingredient mixture to the wet. Use a wooden spoon or spatula to mix until just combined and there are no large clumps of flour, being careful not to over-mix. You can also take a whisk and gently whisk to remove any large clumps of flour!

Gently fold in the chocolate chips.

Pour or scoop the batter into the prepared loaf pan and spread to even the top. Then, sprinkle the chocolate chip cinnamon crumb topping all over the top.

Bake at 350F for 60-70 minutes, until golden and a toothpick inserted into the middle comes out clean. Check the loaf at ~50 minutes; if the top is getting too brown, tent the top with foil.

Remove from the oven and let cool in the pan for at least 10-15 minutes. Then remove and transfer to a serving plate or wire cooling rack.

Slice and serve warm with butter and flaky sea salt, if desired.