Preheat your oven to 350°F (175°C) and generously coat a Bundt pan with baking spray.

In a small bowl, combine the sliced rhubarb, quartered strawberries, cinnamon, and 1/3 cup of sugar. Toss gently and let it sit for about 10 minutes.

Cream together ½ cup of butter and 1 cup of sugar until light and fluffy.

Add room-temperature eggs one at a time and mix in 1 ½ teaspoons of vanilla extract.

Whisk together 2 cups of flour, 3 teaspoons of baking powder, and ½ teaspoon of salt in another bowl.

Mix together ¾ cup of yogurt and 1/3 cup of milk until smooth.

Combine the dry flour mixture with the butter mixture in three parts, alternating with the yogurt mixture.

Layer one-third of the batter in the Bundt pan, add half of the fruit filling, the next third of the batter, remaining fruit filling, and top with the final layer of batter.

Bake for 45-50 minutes, checking for doneness with a toothpick.

Cool in the pan for about 10 minutes, then invert onto a wire rack to cool completely.