• 3 large eggs
• 1 1/2 teaspoons Dijon mustard, or to taste
• 2 1/4 cups plain flour
• 3/4 cup plus 1 1/2 tablespoons whole milk
• 1 1/2 teaspoons coarse salt, or to taste
• 3 1/2 teaspoons chopped tarragon, or to taste
• 2 tablespoons canola oil, plus some for tossing the spaetzle
• 1 tablespoon unsalted butter
• Freshly ground black pepper
• 1 tablespoon pecorino romano cheese, optional
• 1 pound medium sized asparagus, tough ends removed
For the batter:
In a large bowl, whisk the eggs to combine, then whisk in the mustard. Whisk in one-quarter of the flour, followed by one-quarter of the milk, then continue to add the remaining flour and milk alternately until incorporated. Whisk in the salt and 2 1/2 teaspoons of the tarragon. Let the batter rest at room temperature for about 1 hour.
For the asparagus:
Meanwhile, bring a large pot of lightly salted water to a simmer. Prepare an ice bath. Peel the asparagus stalks to within 1/2-inch from the tips. Using kitchen twine, tie the asparagus into 2 bundles. Trim the ends so that they are straight. Add the bundles to the boiling water and simmer for about 2 minutes or until the stalks are almost tender. Remove the bundles and chill in the ice bath. Untie the bundles and transfer to a paper towel lined baking sheet to drain. Slice the stalks crosswise in 1/4-inch slices until you reach the tip. Set the tips and stalks aside separately.
To cook the spaetzle:
Bring a stockpot of lightly salted water to a simmer. Prepare an ice bath. Set up the food mill with the largest disc and place over the stockpot. Pour in the batter and rotate the handle slowly (about 3 seconds per turn), allowing the spaetzle to fall into the water.
Once the spaetzles float to the top, simmer another 30 seconds. Strain the spaetzle and submerge the strainer in the ice bath to chill. Dry on a paper towel lined baking sheet and place in a bowl. Toss the spaetzle with a little canola oil to prevent sticking. If any spaetzle are stuck together, or too large, remove them.
Heat the canola oil in a large skillet over medium high heat. Add the spaetzle and sauté for about 8 minutes, tossing them to brown. Toss in the asparagus stalks, butter, the remaining 1 teaspoon minced tarragon and pepper to taste. Just before serving, toss in the tips and cheese if desired.