Fill a large pot with water and bring it to a boil, adding a generous pinch of salt. Trim the woody ends off the tenderstem broccoli and asparagus, then carefully place them in the boiling water. Blanch these vibrant vegetables for about 3 minutes, until bright green and tender yet crisp. Use a slotted spoon to remove them and set aside.

In the same pot of boiling water, add the pasta. Follow the package instructions for cooking time, generally around 8 to 10 minutes for al dente texture. Stir occasionally to ensure even cooking, and check for doneness a minute or two before the suggested time. When ready, drain the pasta, reserving about a cup of the starchy water for later.

In a large skillet, add 2 tablespoons of butter over low heat, and gently melt it. Once melted, add 3 sliced garlic cloves to the pan, stirring them for about 30 seconds or until fragrant but not browned.

Squeeze the juice of half a lemon into the skillet with the garlic, and add the blanched asparagus, broccoli, and ½ cup of capers. Gently toss everything together.

Add the drained pasta to the skillet, stirring to combine it well with the sautéed vegetables. Gradually mix in a handful of grated Parmesan cheese, adding a splash of the reserved pasta water to create a smooth, cohesive sauce.