There's a simple solution. If the recipe calls for n eggs and you're replacing each egg with 60mL of blood but instead have M mL of blood, make M/(60*N) recipes.

Eg, recipe calls for 2 eggs and you've bled 1.5 L of blood, first do the difficult conversion from L to mL (my witch doctor tells me it's 1500 mL). Now, use the formula: 1500 / (60*2), which simplifies to 25 / 2 or 12.5.

You just need to make 12.5 of your recipe. Just multiply each of the ingredients by 12.5 and you'll be good. Oh and you'll need to adjust cooking time, too, though maybe keep a fire extinguisher handy.