Preheat oven to 350°F (175°C).

Grease a 8x4 inch loaf pan with non-stick cooking spray.

In a separate bowl, sift together flour, baking soda, salt, cinnamon and allspice.

In a large bowl, cream together the margarine and sugars until smooth.

Add the mashed bananas, soy milk mixed with apple cider vinegar, and vanilla extract to the creamed mixture.

Gradually add the dry ingredients to the wet ingredients.

Mix until just combined; do not overmix.

Pour the batter into the prepared loaf pan.

Bake for 60-70 minutes, or until a wooden skewer inserted into the center comes out clean.