Warm 2 teaspoons of oil in a 10-inch non-stick skillet over medium-high heat. When the oil is hot, add the onion and sauté for about 4 minutes until tender and lightly golden. Stir in the garlic and cook for an additional 30 seconds.

Stir in the tomato sauce, chicken broth, chili powder, cumin, paprika, coriander, and salsa. Bring the mixture to a gentle boil, then lower the heat and let it simmer.

Stir frequently until the sauce thickens, reduces by about half, and the onions become tender, approximately 6 minutes. Season with salt and pepper to taste, mix in the sour cream, and toss in the chicken.

Spread a slightly rounded 1/4 cup of refried beans onto the center of each tortilla, leaving about a 2 1/2-inch border around the edges.

Add 1/2 cup of the chicken mixture on top, followed by 3 tablespoons of shredded cheese. Fold in the sides, then fold up the bottom edge tightly and roll to enclose. Secure the ends with toothpicks.

Pour about 1 inch of vegetable oil into a pot and heat over medium-high heat until it reaches 360–365°F.

Once the oil is hot, place two filled tortillas in the pot and fry until the bottom is golden brown. Use metal tongs to carefully flip them over and cook the other side until golden brown as well.

Remove the chimichangas from the oil and let them drain on paper towels, then take out the toothpicks. Repeat the frying process in two more batches with the remaining chimichangas.

Serve warm and garnish with guacamole, diced tomatoes, cilantro, sour cream, salsa, or a drizzle of hot sauce.