In the container of a blender, combine raw egg, lemon zest, lemon juice, vinegar, thyme, and salt; pulse twice. Turn blender on medium speed and slowly and gradually add oil to egg mixture to create mayonnaise. (The mixture will emulsify.) Refrigerate for at least 1 hour.
Using a 2½-inch egg-shaped cutter*, cut 6 egg shapes from frozen bread slices. Cover bread shapes with damp paper towels and let thaw.
Transfer mayonnaise to a small piping bag fitted with an open-star tip (Wilton #18).
Center a hard-cooked egg half, cut side down, onto each bread shape. Pipe beads of mayonnaise** gently around egg halves. Serve immediately, or cover lightly with damp paper towels, place in an airtight container, refrigerate, and serve within 2 hours.
Just before serving, garnish with a light dusting of paprika, if desired.
*We used Easter Egg Cookie Cutter Set of 4 from Amazon.
**Any remaining mayonnaise can be stored in a covered container, refrigerated, and used within 2 weeks.
Notes
KITCHEN TIP: Eggs can be hard-cooked and peeled a day in advance. Place peeled eggs in a deep bowl filled with water and refrigerate until needed. This will prevent eggs from having a flat spot on one side.
Recipe by TeaTime Magazine at https://teatimemagazine.com/egg-canapes/