Scrub the potatoes. Cut each one in half lengthwise. Use a melon baller, sharp measuring spoon, or cookie scoop to scoop the potato flesh out, making a cavity to hold the guacamole.
Put the potatoes into a large bowl. Toss with the 1/2 tsp oil and taco seasoning. I save the scooped out potato insides and roast them on a separate pan, but you could just throw them away.
Spread the potatoes on a baking sheet and bake for 30 minutes, until a fork inserts easily.
Make the Guacamole
While the potatoes bake, make the guacamole. Rinse out the bowl you used for the potatoes and mash the avocados in it. Mix in all the remaining ingredients.
When the potatoes are done and have cooled enough to handle, spoon some guacamole into each one. Garnish with a few cilantro leaves on top or a sprinkle of paprika for a splash of color. Arrange on a platter and enjoy!