Place chicken inside a crock pot. Cover with salsa and drop chicken bouillon cubes on top. Cover and cook on low for 6 hours, or on high for 3-4 hours.
Prepare the jalapeno cream cheese while the chicken is cooking. Combine cream cheese, milk, chopped jalapeno, chicken base paste, and garlic salt in a chopper or food processor until smooth. Keep in the fridge until time to use.
Remove chicken from crock pot and place in a bowl. Use two forks to shred the chicken, then place back in the crock pot with the liquid and stir together.
Preheat the oven to 350° F. Place a tortilla on a plate and add 1/3 c. chicken to the center. Fold the sides in and roll the tortilla to form a chimichanga. If excess liquid starts to ooze out, pour it into the crock pot or a bowl.
Place chimichangas onto a greased cookie sheet seam side down and repeat to make eight. Lightly spray tops with cooking spray and bake for 15 minutes.
Remove chimichangas from the oven and carefully spread jalapeno cream cheese over each one. Top with a slice of cheese and two jalapenos slices. Place back in the oven until cheese is melted. Serve and enjoy!