Preheat your oven to 375°F (190°C) and prepare a bundt pan by greasing it with unsalted butter and dusting it with flour.

In a large mixing bowl, beat together the softened unsalted butter and granulated sugar using an electric mixer until light and fluffy, about 2-3 minutes.

Add the eggs, vanilla extract, and plain Greek yogurt to the creamed mixture, mixing until smooth.

In a separate bowl, whisk together the all-purpose flour, baking soda, and salt.

Slowly add the dry ingredients to the wet mixture, mixing on low speed until just combined.

Gently fold in the semisweet chocolate chips using a spatula.

In a small bowl, mix the brown sugar and ground cinnamon until well combined.

Pour half of the cake batter into the prepared bundt pan, sprinkle with half of the cinnamon swirl mixture, swirl gently, then add remaining batter and top with the rest of the cinnamon mixture, swirling again.

Bake for 25-30 minutes or until a toothpick comes out clean.

Allow the cake to cool in the pan for about 10 minutes before inverting onto a wire rack to cool completely.