Heat a large pot (dutch oven) over medium-high heat. Add 1 tablespoon of olive oil. Season the roast, liberally with salt and pepper, on both sides. Coat in flour and shake excess. Place in the heated oil and sear for about 5 to 7 minutes per side, until the outside develops a crispy and brown crust. Transfer the roast to a plate or platter to rest.

Add 1 tablespoon more of oil and throw in the onions and garlic. Cook for a few minutes until the onions have softened. Add the rest of the vegetables, celery, carrots, potatoes, mushrooms, leeks, bay leaves, and thyme sprigs. Season with a bit of salt and pepper. Sauté for a few minutes until the fews begin to softened, but not all the way. Transfer the veggies to a platter or plate. Add the rest of the oil and cook the tomato paste for a few minutes until it gets bright red. Throw in the ⅓ cup flour, wine and beef stock. Whisk until it's completely smooth. Season with a bit of salt and pepper. Cook, stirring frequently, over medium heat, until it has thickened and become smooth. Place the roast, veggies, and sauce in a slow cooker and cook on low for about 8 hours. Or you can combine everything in a heavy duty pot, cover it and place in a 275° oven for about 4 to 5 hours, or until the meat is tender and soft. Once the roast has cooked, slice it and arrange with the sauce and veggies.

Meanwhile for the aioli, combine the egg, lemon juice, garlic and mustard in a food processor or blender. Blend until completely smooth. While the blender or food processor is running, slowly stream in the oil until it has thickened. Add the sriracha and season with a bit of salt and pepper. Purée once more to combine. Taste and adjust seasonings. Will keep in the fridge, in an airtight container for about 1 week.

For the crispy onions, heat a deep pot or skillet with high sides over medium-high heat, filled with about 3 inches of oil, enough for frying.

In large bowl combine the sliced onions with the buttermilk. Make sure they're well coated. In a shallow dish, whisk together the flour and seasonings. Coat the buttermilk soaked onions with the seasoned flour, a few at a time. Don't crowd the dish, you want to make they're completely coated. Shake off the excess flour.

Fry the coated onions in batches, for about 3 to 4 minutes per side, or until golden brown and crispy. Drain off excess oil and transfer to a plate lined with paper towels. Place the fried onions on a baking sheet and keep warm in a low oven, until ready to eat.

To make the sliders, warm the buns and slice them in half. Slather the bottom half with sriracha aioli, place a few slices of cheddar cheese. Top with some of the pot roast (veggies included). Add some crispy onion rings. Spread the top bun with smashed avocado and top the slider. Spear a long tooth pick to keep them together. Serve warm or at room temperature. Enjoy!