Hello everyone great to join this site

I have a question regards the use of home-made bases.
I plan to make a Schwartz slow cooker chicken curry tomorrow and was wondering if I can add a base that I have made to it. The recipe to the base I have made is:
5 large onions chopped.
5 cloves garlic.
400g tin tomatoes.
1 teaspoon turmeric.
1 teaspoon cumin.
1 teaspoon paprika.
Oil
I have divided the mix up into four equal measures about a cup full in each frozen three and have one in the fridge.
Now do I just make the Schwartz recipe as it says on the packet and add the base to it? The recipe calls for another tin of tomatoes will adding the base mean it will have too much tomato? As you can see I am new to all this so please have a little patience if you consider this a stupid question.
Thank you.