Preheat your oven to 350°F (175°C). Grease a 9-inch round cake pan to prevent sticking.

In a medium bowl, sift together the flour, baking powder, and salt. Set this aside for later.

In a large bowl, cream the softened butter and granulated sugar together using an electric mixer at medium speed. Beat until the mixture is light and fluffy, typically about 4-5 minutes.

Add the eggs one at a time to the butter-sugar mixture, ensuring each egg is well incorporated before adding the next. Stir in the vanilla extract.

Gradually mix the dry ingredients into the wet mixture, alternating with the milk. Start and end with the dry ingredients, mixing until just smooth. Avoid overmixing, as this can make the cake dense.

Gently fold in the chopped rhubarb with a rubber spatula or wooden spoon until evenly distributed throughout the batter.

Pour the batter into the prepared cake pan and smooth the top with a spatula for even baking.

Bake for 30–35 minutes, or until the top turns golden brown and a toothpick inserted into the center comes out clean.

Once baked, let the cake cool in the pan for about 10 minutes. Afterward, carefully transfer it to a wire rack to cool completely.

Optionally, once fully cooled, dust the top with powdered sugar for an extra touch of sweetness and elegance.