Preheat your oven to 350°F (175°C) and prepare a 9x5 inch loaf pan by greasing it or lining it with parchment paper.

In a medium bowl, whisk together the flour, baking powder, baking soda, and salt until combined.

In a large mixing bowl, cream the butter and sugar with an electric mixer until light and fluffy.

Add the eggs one at a time, mixing well after each addition. Stir in lemon juice, lemon zest, vanilla extract, and sour cream.

Fold the dry ingredients into the wet mixture until just combined.

Fold in the chopped fresh rhubarb gently into the batter.

Pour the batter into the prepared loaf pan and smooth the top.

Bake for 50-60 minutes, checking with a toothpick for doneness.

Let the loaf cool in the pan for about 10 minutes before transferring it to a wire rack to cool completely.

While cooling, mix powdered sugar with enough lemon juice to form a glaze.

Drizzle the glaze over the cooled loaf.