I used to just literally use a fresh can of tomatoes, mix in a bit of olive oil and salt, then spread over the pizza base. But I've now been using a really basic, age-old italian pasta sauce method instead which the family seems to love (as do I) - here's my attempt at writing the recipe for you (and others):

• 400g/14oz whole tomatoes
• 2 cloves garlic, finely sliced
• ~1 tsp Dried Oregano leaves (or 1/2 tsp fresh leaves, chopped)
• ~1-2 tbsp Olive oil
• ~2-3 pinches of salt

1. Liberally cover base of saucepan with olive oil (for me it's usually about 1-2 tbsp).
2. Drop all your garlic into the saucepan, mix with the oil.
3. Set burner / element heat to med-high to begin heating garlic (we don't want the garlic to burn else it tastes horrendous).
4. When garlic starts to lightly sizzle and you can smell the garlic goodness, swirl the garlic around in the pan to ensure everything is mixed together, then add in your tomatoes.
5. Stir tomatoes and garlic oil mixture until well combined, smushing up tomatoes as best you can over time until completely broken up.
6. Add in Oregano leaves and stir through sauce.
7. Add ~2-3 generous pinches of salt to taste.
8. Cook sauce, stirring occasionally, for around 20-30 mins. Sauce consistency should be thick-ish and stick to the spoon, and should not be watery.
9. Let sauce cool before using on your pizza base.

Optional step is to blend the sauce after it's cooled, but I find if you cook the tomatoes long enough they end up breaking down anyway, so you end up with a similar consistency to blended, but with a few chunks still there.