This is a delicious, light, creamy soup perfect for a cold evening!
In a large dutch oven melt 1 tbsp butter over medium heat. Add leeks and saute 4 minutes. Add asparagus, stir to combine, and season with 1/2 tsp kosher salt. Continue to saute 4 minutes.
Add flour and stir to coat. Saute for 2-3 minutes, until it barely starts to bubble.
Add chicken stock. Bring just to a boil. Simmer 5-10 minutes until asparagus is al dente (or to your desired doneness).
Add warmed cream, and stir to combine. Turn off heat. Season with 1/4 tsp white pepper and 1 tsp kosher salt.
Melt in 1 tbsp butter. Add Parmesan cheese and tarragon.
Note: To make a lighter version of this soup, substitute half and half for heavy cream, and reduce butter by 1 tbsp