Preheat your oven to 350°F (175°C). Spread the 2 cups of pecan halves evenly on a large, ungreased baking sheet. Toast for 6 to 8 minutes, shaking the pan once halfway through, until they are fragrant. Remove the pecans and let them cool completely.

Prepare two large baking sheets by lining them with parchment paper or silicone baking mats. Lightly grease the parchment paper with the 1 tablespoon of unsalted butter. Arrange the cooled, toasted pecan halves onto the prepared sheets in small clusters of four to six pecans each, forming small circular 'nests' spaced at least two inches apart. You should yield approximately 24 to 30 clusters.

Place the unwrapped caramels and the 2 tablespoons of heavy cream or milk into a medium, microwave-safe bowl. Microwave the mixture in 30-second intervals, stirring thoroughly after each interval, until the caramel is completely melted and smooth (typically 90 seconds to 2 minutes). Stir in the vanilla extract, if using.

Working quickly before the caramel sets, use a teaspoon to spoon a generous dollop of the warm caramel mixture directly over the center of each pecan cluster, ensuring the caramel binds the nuts together.

Allow the caramel-coated pecan clusters to set and cool completely at room temperature for about 30 minutes, or place them in the refrigerator for 15 minutes to speed up the setting process.

Place the chocolate wafers or chips and the optional coconut oil/shortening in a clean, dry microwave-safe bowl. Melt the chocolate by microwaving on 50% power in 30-second intervals, stirring well until the chocolate is smooth and entirely melted.

Use a fork or a dipping tool to carefully pick up one cooled caramel pecan cluster at a time. Dip the cluster into the melted chocolate, coating the bottom and sides thoroughly, typically leaving some of the caramel and pecans visible on top (traditional turtle style).

Lift the coated cluster out of the chocolate, allowing any excess to drip back. Place the coated turtle cluster back onto the parchment-lined baking sheets. Immediately sprinkle a small pinch of flaky sea salt over the wet chocolate (if desired).

Allow the chocolate pecan turtle clusters to set completely at room temperature (several hours) or chill them in the refrigerator for about 30 to 45 minutes until the chocolate is firm and snaps cleanly. Store in an airtight container at room temperature for up to one week.