In a pan on medium-low heat, add the olive oil (or butter), garlic and lemon zest. Cook, stirring, so the garlic and zest can steep without browning, about 5 minutes. Add the lemon juice, thyme, a pinch of salt and a few more grinds of black pepper than you normally would. Move the contents of the pan around a bit more while cooking, until the thyme is darker in color and the pan is fragrant, about 5 more minutes.
Add the peas and toss to warm and coat, about 4 minutes. Pour into a serving dish and top with the cheese.