Prepare the Oven and Pan: Preheat the oven to 400°F. Line a rimmed baking sheet completely with aluminum foil.
Grate the Cheese: Shred the Monterey Jack cheese using the large holes of a box grater.
Remove the Sausage Casings: Cut a shallow slit down the side of each sausage link. Peel away and discard the casings, then place the sausage meat in a large mixing bowl.
Add the Cheese: Add the shredded Monterey Jack cheese to the sausage.
Add the Baking Mix: Pour the all-purpose baking mix evenly over the sausage and cheese.
Add the Jalapeños: Add the diced jalapeño peppers to the bowl.
Add the Garlic: Spoon the chunky garlic paste into the mixture.
Add the Green Onions: Add the sliced green onions.
Combine the Mixture: Stir the ingredients with a wooden spoon until they begin to come together. Finish mixing with clean hands, if needed, until the sausage, cheese, baking mix, and vegetables are evenly distributed.
Portion the Poppers: Use a small cookie scoop to divide the mixture into 24 equal portions, about 1½ tablespoons each.
Shape the Poppers: Gently roll each portion between your palms to form a compact ball. Arrange the poppers on the prepared baking sheet with a little space between them.
Bake the Poppers: Bake for about 15 minutes, or until the poppers are golden, cooked through, and reach an internal temperature of 160°F in the center.
Serve Warm: Let the sausage cheese poppers cool for 2 to 3 minutes, then transfer them to a serving dish and serve warm.