In a large mixing bowl, combine the Bisquick mix, milk, eggs, sugar, baking powder, vegetable oil, and vanilla. Stir together just until combined. Be careful not to overmix; a few lumps are perfectly fine! The batter will be thick and smooth.
Next, heat a lightly oiled griddle or nonstick frying pan over medium-high heat. It's important to get the pan hot enough so the pancakes cook evenly. You can test the heat by flicking a few drops of water onto the surface; if they dance and evaporate, you're ready to go!
Now, pour or scoop the batter onto the griddle. Use approximately 1/4 cup for each pancake. Make sure to leave space between each pancake, as they will spread a little while cooking. You'll know it's time to flip them when you start seeing bubbles on the surface, and the edges look dry.
Carefully flip each pancake using a spatula. Cook until they are browned on the underside, which should take about 2 minutes. Keep an eye on the color; you want a beautiful golden-brown hue.
Once cooked, transfer the pancakes to a baking sheet and keep warm in the oven while you repeat the process with the remaining batter. Depending on your pan size, you might need to grease it with additional oil between batches to prevent sticking.
When all your pancakes are cooked, stack them high on a plate and get ready to enjoy! You can serve them with your favorite toppings like syrup, fruit, or whipped cream. Each bite is a taste of nostalgia wrapped in happiness.