Start by heating the oven to 350°F (175°C). Prepare a 9×5-inch loaf pan by greasing it or lining it with parchment paper. In a large mixing bowl, stir together the flour, baking powder, salt, and sugar until the ingredients are evenly mixed.
In a separate bowl, whisk the milk, vegetable oil, and eggs until smooth. Slowly add this liquid mixture to the dry ingredients, stirring gently until the batter comes together.
Add the shredded cheddar, crumbled bacon, and chopped green onions, folding them into the batter carefully. The batter should remain slightly lumpy.
Transfer the batter into the prepared pan, spreading it evenly on top. Place in the oven and bake for 40 to 45 minutes. Check for doneness by inserting a toothpick into the center; it should come out clean.
Let the loaf rest in the pan for about 10 minutes, then move it to a wire rack to cool fully. Slice and enjoy either warm or at room temperature.