In an 8 ounce canning jar, combine chive flowers and garlic cloves. Fill jar with vinegar, leaving about 1 inch space at the top. Use a spoon to press chive flowers against side of jar, breaking them up just a little. Cover top with parchment paper and then close with lid. Let sit in a cool, dry place for at least 1 week.
For the frittata:
Preheat oven to 350F.
Bring a pot of heavily salted water to boil. Add asparagus and boil for 3 minutes. Transfer asparagus to a bowl and cover with ice water. Let cool completely.
In a large bowl, whisk together eggs, milk, salt and pepper. Set aside.
In a 10 inch cast iron skillet, heat olive oil over medium heat. Add the spring garlic and cook until fragrant, about 1 minute. Add egg mixture and chives and stir to distribute greens evenly. Cook for 5 minutes over medium heat, until edges start to set. Remove from heat and arrange asparagus spears, all pointing towards the center, in the eggs and dollop goat cheese around the entire pan. Transfer pan to oven and bake for 15-20 minutes, until center is just set. Make sure to watch as you don’t want the eggs to overcook!
To make the salad: While frittata is baking, prepare the salad. In a small bowl, whisk together 4 tbsp olive oil and 4 tsp infused vinegar. Pour over 6 oz greens and add salt and pepper to taste.