Prepare all the ingredients. Start by cutting the day-old white bread into small cubes, about 1/4 inch on each side. Do the same with the asparagus, but chop them into pieces about 1/8 inch (2-3 mm) on each side. Make sure not to cut them larger, or the canederli may fall apart.

In a skillet, melt the butter. Once melted, add the finely chopped onion and cook for a few minutes until softened. Then add the asparagus, sauté well, remove from heat, and let cool.

In a large bowl, combine the cooled contents of the skillet with the bread cubes and mix. Add the milk and the previously beaten egg, and mix again.

Add the finely chopped parsley, salt, and pepper. Gently mix and check the dough: if it's too soft, add some breadcrumbs; if it's too firm, add a little more milk. The mixture should be compact, not mushy.

Once everything is well combined and the texture is right, cover with plastic wrap and let rest for at least 15 minutes. After resting, add the flour. Do not use more than 1 tablespoon (15 g) for these amounts, or the canederli will become tough when cooked.

Scoop out a heaping tablespoon or more of the mixture and shape into round, compact balls. You should get about 6 canederli with these amounts, unless you make them smaller.

Bring a large pot of salted water to a boil. Gently drop in the canederli and boil for 10 minutes, stirring very gently 2 or 3 times. When cooked, drain the canederli well and place them on a plate.

After cooking, remove the vegetables and let the broth rest for about 15 minutes so any impurities settle at the bottom. Then strain the broth carefully without disturbing the sediment. Your consommé is ready.