In a small saucepan, combine lemon juice, carrot juice, and chicken or vegetable broth. Heat over medium until warmed, gently stirring.

In a large skillet, melt butter over medium-high heat. Add finely diced onions and carrots, cooking for 5-7 minutes until softened.

Stir in the orzo to the sautéed vegetables, toasting for 1-2 minutes until slightly golden.

Pour in the white wine, stirring until fully absorbed by the orzo, about 2-3 minutes.

Ladle in the warmed broth mixture, one scoop at a time, stirring frequently until absorbed, for about 30 minutes.

Season with salt to taste. Remove from heat and let rest for a couple of minutes before serving.