Can I substitute a 10 oz bag of large marshmallows for the same weight equivalent in miniature mallows?
Culinarily speaking, large marshmallows are identical ounce-for-ounce to miniature marshmallows, so for the purpose of an ingredient substitution, this should not cause you a problem. But there are a few things to consider:

Miniature marshmallows are obviously smaller&hellip; so if your recipe calls for using them whole, you may have to decide if the larger versions are appropriate for your recipe.

Miniature marshmallows are also easier to melt, so if you are adding larger pieces to a hot mixture, you may have to take extra care they are melting completely. And if you are melting them over heat, be sure the extra time required does not cause them to burn. 

And just for the sake of completeness, marshmallows are also coated in corn starch to prevent them from sticking to one another. Since miniature marshmallows have a bit more surface area, you may end up with just a bit less cornstarch in your mixture. But it seems highly unlikely this will make a difference in your final product.