Measure your flour, salt, garlic powder, parsley, and baking powder into a big bowl. Stir the dry ingredients together so that they are evenly distributed throughout the flour. Now, pour in the milk. Stir with a big spoon until you have a ball of dough that leaves the sides of the bowl. You may have to dust the ball of dough with a little flour if it seems sticky to you. Gently knead the ball of dough right there in the bowl 5 or 6 times. Now place your dough on the counter. You may use a piece of waxed paper under the dough if you like. Using a rolling pin roll out the dough to a rectangular shape. If the edges become uneven, use your hands to reshape into a rectangle. It doesn't have to be perfect. You are aiming for a rectangle that will fi into a 9- by 13-inch pan. When you get the dough the right size, set it aside.
Meanwhile, place the margarine in the 9- by 13-inch pan and place the pan in a 425F oven to melt the margarine. When the margarine is melted, carefully remove the pan from the oven, so as not to burn yourself. Sprinkle the second teaspoon of garlic powder and the 1/2 teaspoon of salt into the pan. You do not have to use the extra salt. Now, very carefully, lay your rectangle of dough into the pan, over top of the margarine. Next cut the rectangle into narrow strips. One method of doing this is to cut the dough in half, then cut each half again, quartering the dough, and then cut each quarter into narrow strips. The margarine will creep up between the strips. This is normal. It is what gives these bread sticks their texture. After cutting your strips, place the pan in the oven, still at 425F, and bake them for 20 minutes. They will be browned and crispy when they are done.
The parsley is simply for decoration. It makes the bread sticks look more gourmet, but it adds little to the flavor or the texture. Leave it out if you don't have any, or are running low. If desired, you may sprinkle the bread sticks with a little bit of parmesan cheese before or after baking. This tastes good, but once again, is optional.