Preheat the oven to 350°F. Spread the pecan halves evenly across a baking sheet.
Toast the pecans for 5–10 minutes, stirring once during baking, until fragrant and lightly toasted. Alternatively, toast them in a hot skillet for about 5 minutes, stirring continuously.
Allow the toasted pecans to cool, then roughly chop them with a knife. Set aside.
Line a baking sheet with parchment paper or a silicone baking mat.
Place the salted butter in a large microwave-safe glass bowl and microwave until completely melted.
Add the packed brown sugar, granulated sugar, sweetened condensed milk, and light corn syrup. Stir thoroughly until well combined.
Microwave on HIGH for approximately 6–8 minutes, or until the caramel reaches about 235°F on an instant-read thermometer.
If using the cold-water test, drop a small spoonful of caramel into ice water. Once safely cooled, it should form a soft ball when gently pinched. If it doesn't hold its shape, microwave for another 30 seconds and test again.
Carefully remove the hot bowl using oven mitts. Add the vanilla extract and stir until incorporated.
Add the roughly chopped toasted pecans to the hot caramel and mix until evenly coated.
Drop large spoonfuls of the caramel pecan mixture onto the prepared baking sheet, forming approximately 20 individual clusters.
Refrigerate for about 20 minutes, or until the caramel has firmed up.
Place the almond bark or high-quality chocolate in a microwave-safe bowl. Microwave in 30-second intervals, stirring after each interval, until completely melted and smooth. Alternatively, use a double boiler.
Using a fork, dip each chilled caramel pecan cluster into the melted chocolate, turning gently until completely coated on all sides.
Lift each chocolate-covered cluster out with the fork and lightly tap it against the bowl to let the excess chocolate drip off.
Transfer the coated turtles back onto the parchment-lined baking sheet and allow the chocolate to set completely before serving.