There used to be “no-doc” loans available for people in your situation. I know of one or two lenders that used to lend up to 95% of the purchase price of a home without asking whether you had any source of income and without asking you where the down-payment money was coming from. These lenders are now either gone or have eliminated those programs.
There are still “stated income” programs around which allow you to state what you earn without having to prove it. However, for these programs you typically need from 20% to 25% down and you still have to prove that you are employed. Since you get paid in cash, I would venture to say that your employer probably would not be willing to memorialize your employment relationship, that is, put it in writing.
The other possibility is to apply for a “full doc” loan and to verify your income on the basis of your tax returns. You’ll need to find yourself an experienced and knowledgeable loan officer who knows how to interpret them since there are deductions people take which can be added back to your adjusted gross income for loan qualifying purposes.