I have very fair porcelain skin and know all about the dark circle issue...
I have had best luck with either Estee Lauder's cream concealer (in a wand...not even sure they have this anymore but it was amazing), and more recently L'Oreal's Hydra Perfecte concealer with SPF 12 (in a tube). Either of these blends great into my foundation.
The one thing I have learned is that it's best to get a very light concealer and use it sparingly. A concealer that is slightly different from your foundation will give you yet a 3rd color when both are blended together. Rather, a very light concealer + foundation = a lightened under eye area (but sparingly applied so it doesn't look too fake).
I have had best luck with either Estee Lauder's cream concealer (in a wand...not even sure they have this anymore but it was amazing), and more recently L'Oreal's Hydra Perfecte concealer with SPF 12 (in a tube). Either of these blends great into my foundation.
The one thing I have learned is that it's best to get a very light concealer and use it sparingly. A concealer that is slightly different from your foundation will give you yet a 3rd color when both are blended together. Rather, a very light concealer + foundation = a lightened under eye area (but sparingly applied so it doesn't look too fake).