Preheat your oven to 350°F (175°C) and grease a baking dish (8x8 inches) lightly.
In a mixing bowl, combine the softened cream cheese and shredded cheddar cheese. Mix until smooth using a whisk or electric mixer.
Add the eggs to the cheese mixture and continue mixing until well combined.
In another bowl, sift together the flour, baking powder, garlic powder, salt, and black pepper.
Gradually add the dry mixture to the wet mixture, stirring gently until just combined.
Fold in the diced jalapeños until evenly distributed.
Pour the batter into the prepared baking dish and spread it evenly with a spatula.
Bake in the preheated oven for about 25 minutes, or until the top is golden brown and a toothpick inserted in the center comes out clean.
Let it cool for 10 minutes before cutting into squares.