Put a large deep skillet or wide saucepan on the stove over medium heat.

Start the base: Add the butter to the skillet. When it melts, add the shallot and a small pinch of salt.

Cook the shallot for 2 to 3 minutes, stirring often, until it looks soft and no longer raw.

Add the dry orzo to the skillet.

Toast the pasta: Cook the orzo for 1 to 2 minutes, stirring often, until some pieces smell nutty and look a shade darker.

Pour the broth into the skillet and scrape the bottom with a wooden spoon so nothing sticks.

Raise the heat to medium-high and bring the broth to a boil.

Cook the orzo: Once the broth is boiling, lower the heat to medium-low so the liquid bubbles gently.

Cook for 5 minutes, stirring every minute or so, until the orzo starts to swell and the broth looks slightly thickened.

Add the frozen peas to the skillet and stir them into the orzo.

Cook for 3 to 4 minutes more, stirring often, until the orzo is tender and most of the liquid has turned into a light, creamy sauce.

Finish the skillet: Turn off the heat. Stir the lemon zest into the skillet, then squeeze in juice from one lemon half.