Preheat oven to 350°F. Line 8 jumbo muffin cups with parchment or paper liners, or spray with cooking spray.
In a large bowl, whisk together flour, baking powder, and salt. Make a well in the center of mixture. In a small bowl, whisk together egg and buttermilk. Add to dry ingredients, stirring just until moistened. Fold in all remaining ingredients.
Spoon batter into prepared muffin cups. Bake until a wooden pick inserted in center comes out clean, 25 to 30 minutes. Let cool in pans for 5 minutes. Serve warm or at room temperature.
Recipe by Bake from Scratch at https://staging.bakefromscratch.com/bacon-cheddar-poppy-seed-muffins/