Cut both onions in half. Thinly slice 3 of the halves and dice the remaining half. In a pan on medium high heat at 1 tbsp of olive oil. Cook the diced onions 3-5 minutes until golden and softened. Add cooked onions to the ground turkey. Place the pan back on the heat and add another 1 tbsp of olive oil. Add the sliced onions to the pan. Stir the onions every 3-5 minutes for about 15 minutes (don't stir continuously, you want them to caramelize rather than steam). Tip: Add 1 tsp of water to onions when they're done cooking to de-glaze the pan.
Add ketchup, 2 tbsp chipotle, smoked paprika, salt and pepper to ground turkey. Mix until evenly combined. Form 10 slider patties. In a pan (cast iron pan works best) on medium-high heat add 1 tbsp olive oil. Cook 3-5 minutes on one side the flip. A crispy crust should form before flipping. Tip: The meat will let you know when it's ready, if it's sticking to the pan when you try to flip it, it's not ready.
Top each slider with cheese slices and reduce heat to medium. Cover the pan to allow the cheese to melt, about 2-3 minutes.
In a small bowl mix Greek yogurt or smashed avocado with 1/2 tbsp of chipotle. Add salt and pepper to taste.
Toast buns. Dunk the bottom bun in the pan juices/melted cheese. Top with slider and caramelized onion slices. Smear chipotle yogurt or avocado on the top bun. Enjoy!