Dice the scallops in 1/4-inch cubes.
Mince the jalapeno and combine it with the olive oil.
Wash the radishes, slice them in 1/4-inch strips, then slice them again lengthwise into tiny batons.
Mix all the ingredients except the tarragon flowers together and season to taste.
Allow the scallops to marinate with everything for at least 1 hour in the fridge. The lime juice will "cook" the scallops, and the flavors will meld together.
Finally, spoon the ceviche into shot glasses and serve with a small spoon. Garnish with tarragon flowers (optional).