I have used many different under eye concealers through the years, but I always turn back to Yves Saint Laurent's Touche Eclat.
This golden tube of luxury is actually categorised as a highlighter, but I tend to use to to disguise dark circles under my eyes due to its light-reflecting ways.
It has a light, fluid texture which blends easily under the delicate eye area. I usually click the pen a few times to dispense some product, paint from the inner corner of the eye to the outer corner, leave for a few seconds and then pat into place.
I also use the product to highlight below the brow bone and sometimes on the sides of the nose to disguise redness.
I instantly look more awake after applying this stuff, so it's a must for me in the mornings!
I use the Shade 2 - Luminous Ivory - which is a great match for my pale skintone.
Available from Yves Saint Laurent counters nationwide, €35.