The Blinker cocktail recipe was first published in 1934 and was recently republished in Robert Simonson's 3-Ingredient Cocktails. In the video below I used ruby red grapefruit juice which is typically sweeter than plain grapefruit juice - this worked in my favour as the drink did need an increase of the sweet component. Adjust the amount of raspberry syrup depending on the strength and sweetness of your syrup.

Homemade raspberry syrup preferred of course!