Begin by cooking the bacon in a skillet over medium heat until crispy, about 6-8 minutes. Once cooked, remove and chop into small pieces. Sauté fresh spinach briefly in the same skillet until wilted, around 1-2 minutes.

In a medium mixing bowl, combine the all-purpose flour, baking powder, baking soda, salt, and black pepper, whisking to blend well.

In a large bowl, whisk together the milk, plain yogurt, and olive oil until smooth and lump-free, about 2-3 minutes.

Gradually add the dry ingredients to the wet mixture, folding gently with a spatula until just combined.

Fold in the crispy bacon, sautéed spinach, shredded cheddar cheese, and chopped chives until evenly distributed.

Preheat your oven to 350°F (175°C). Grease a muffin tin or line it with paper liners. Divide the batter among the muffin cups, filling each about three-quarters full. Bake for 20-25 minutes until golden brown and a toothpick comes out clean.

Once baked, cool in the tin for about 5 minutes, then transfer to a wire rack to cool completely. Enjoy warm or store in an airtight container.