Prep the slow cooker. Grease the crock with butter or nonstick spray. For easier cleanup and cleaner edges, line with a parchment sling and grease the parchment as well.

Cube the bread. Cut bread into 1-inch cubes. If the bread is fresh, spread cubes on a sheet pan and air-dry for 1–2 hours, or toast lightly at 300°F for 10–12 minutes. Dry bread soaks better.

Whisk the custard. In a large bowl, whisk eggs. Add pumpkin, milk, cream, brown sugar, granulated sugar, vanilla, pumpkin pie spice, cinnamon, salt, and melted butter. Whisk until smooth and well combined.

Combine with bread. Place bread cubes in a large mixing bowl. Pour the custard over the top and toss gently to coat. Let it sit for 10–15 minutes, stirring once or twice, so the bread absorbs the custard.

Add mix-ins. Fold in raisins, cranberries, nuts, or chocolate chips if using. Keep the mix-ins under 1 cup total so the pudding sets properly.

Fill the crock. Transfer the mixture to the prepared slow cooker. Spread into an even layer and gently press down to compact slightly. This helps the custard set evenly.

Cook low and slow. Cover and cook on LOW for 3–4 hours or on HIGH for 2–2 1/2 hours, until the center is set and no longer overly jiggly. A knife inserted near the center should come out mostly clean with a few moist crumbs.

Vent near the end. In the last 30 minutes, prop the lid slightly with a wooden spoon to let steam escape. This helps prevent a soggy top and encourages gentle browning around the edges.

Rest before serving. Turn off the slow cooker and let the pudding rest, uncovered, for 10–15 minutes. It will firm up as it cools slightly.

Serve warm. Spoon into bowls and top with whipped cream, ice cream, or a dusting of powdered sugar. A drizzle of warm caramel sauce is excellent.