During the recess, the Departmentally Related Standing Committees of Parliament examine the Demand for Grants submitted by various Ministries.  The Demand for Grants are detailed explanations of that Ministry's annual budget which form part of the total budget of the government.  These are examined in detail, and the committees can approve of the demands, or suggest changes.  The Demand for Grants are finally discussed and voted on by the Parliament after the recess.  (The post below lists the ministries whose Demand for Grants will be discussed in detail after the recess). The issue is - how effective is the institution of Parliament in examining the budget?  Though India specific information on this subject is hard to find, K. Barraclough and B. Dorotinsky have cited the World Bank - OECD Budget procedures Database to formulate a table on the legislature approving the budget presented by the executive ("The Role of the Legislature in the Budget Process: A Comparative Review", Legislative Oversight and Budgeting).  I reproduce the table below:

In Practice, does the legislature generally approve the budget as presented by the Executive? (in percent)
Answer All Countries OECD Countries Presidential democracies Parliamentary democracies
It generally approves the budget with no changes 34 33 14 41
Minor changes are made (affecting less than 3% of total spending) 63 67 71 59
Major changes are made (affecting more than 3% but less than 20% of total spending) 2 0 7 0
The budget approved is significantly different (affecting more than 20% of total spending) 0 0 0 0
Sources:  K. Barraclough and B. Dorotinsky; PRS.

Apropos Madhukar’s post on available information on the functioning of state legislatures, data on the number of days State Assemblies shows a mixed trend over the 2000 to 2010 period. However, most states uniformly under perform when it comes to number of days of sitting. (Spreadsheet with relevant data here) As with Parliament, state assemblies are convened at the will of the executive. In comparison to the Lok Sabha, the state assemblies perform miserably. In any given year, most state assemblies do not sit for even half the number of the days clocked by the Lok Sabha.