Crisp the bacon: In a skillet over medium heat, cook the chopped bacon until crisp. Transfer to a paper towel–lined plate. Spoon about 1 tablespoon of the bacon fat into the slow cooker for extra flavor; discard the rest or save for another use.

Sauté aromatics (optional but recommended): In the same skillet, melt the butter and sauté the onion for 3–4 minutes until translucent. Add the garlic and cook 30 seconds. Transfer to the slow cooker.

Load the slow cooker: Add the broccoli, chicken broth, smoked paprika, and ground mustard. Stir to combine. Cover and cook on low for 4–5 hours or high for 2–3 hours, until the broccoli is very tender.

Blend to your preferred texture: Use an immersion blender directly in the slow cooker to puree until smooth, or leave some chunks for texture. If you don’t have an immersion blender, carefully transfer in batches to a countertop blender and return to the slow cooker.

Add the creamy elements: Stir in the cream cheese until melted and smooth. Add the heavy cream and half of the shredded cheddar. Stir on low heat until fully melted and velvety.

Finish with cheese and bacon: Add the remaining cheddar and most of the bacon (save some for garnish). Stir gently until melted. Taste and season with salt and black pepper.

Serve: Ladle into bowls and top with bacon crumbles, extra cheddar, and chives if you like. The soup will thicken slightly as it cools.